"A "cool" tool with severe drawbacks."

[[folder:Automotive & Aeronautics]]
* On land, driving beyond the speed-limit is generally this. It's so cool and rebellious to blaze down a high-way like you're playing VideoGame/NeedForSpeed, and probably a thrill. However, you're obviously vulnerable to being pulled over by the police, the citation you get can add even more expense by raising your insurance rates, and it's up to the individual cop if they feel like going easy on you.\\
However, the physical dangers are what can truly ruin you day. Exceeding the speed-limit makes it more likely to lose control of your vehicle in emergency situations, increases your braking distance and likelihood of crashing into the back of a vehicle in a sudden traffic jam, and generally reduces your margin for error. Speeding is also not as much of a time-saver as you may think, and can create an unhealthy level of stress.
* "Chopper" motorcycles often fall under this heading. The more extreme the styling, the less practical they are to actually ride. Many of the prize-winningest show bikes don't even have real engines in them, and couldn't be ridden if they did.
* Some car fans - particularly those who own coupes and other economy-level cars - like to add what is known by detractors as [[RiceBurner rice]]: flashy-looking extra bits that make the car look like it's seriously fast, but that are usually ill-researched and badly designed, so they only end up messing up the aerodynamics and making the car go ''slower''.
** Spoilers on a front-wheel drive car are particularly stupid - getting enough downforce to activate the spoiler would actually ''reduce'' performance by pulling the drive axle off the ground.
* The Reliant Robin was an entirely plastic three wheeled car from the 70's. It was very light weight, it was legally a motorcycle in its origin nation of the U.K. (meaning a Reliant owner had to pay less on taxes and didn't need a driving licence), and was very popular in the Northern parts of Britain. Problem was, the single wheel (used for steering) was in the front, along with the engine, making it both nose-heavy and unstable. It was alarmingly prone to wobbling when going around corners, or making any sudden, sharp turn.
* Sedans with standard trunks. Yes, they look awesome and provides large boot space to many Americans and Asians (particularly Chinese), but for Europeans, [[AmericansHateTingle it's impractical in terms of space.]] Hatchbacks and station wagons provide greater rear cargo space for roughly the same amount of car, or the same amount of cargo room in a smaller package, a huge deal on a continent where space is often at a premium.
** Funnily enough, in the United States, nearly the inverse is true. European micro-cars theoretically save a ton of space and gas, but often aren't practical for American drivers. This is mostly because, while American fuel economy standards are fairly lax, American ''emissions'' standards are some of the toughest in the world, a fact that many people tend to ignore. And California's standards are the strictest of all. (This is the reason why [[http://www.wsj.com/articles/los-angeles-sees-health-benefits-as-its-smog-haze-clears-1425506401 you rarely hear]] about UsefulNotes/LosAngeles' once-notorious smog anymore.) The fuel-sipping, yet highly polluting, diesel engines that power many of these Euro-compacts often have to be {{nerf}}ed into oblivion in order to pass inspection, as Volkswagen found out the hard way in 2015. Ditto for American crash safety standards; that "wasted" space in the back of a sedan is actually very useful for preventing injury to a car's occupants in the event that [[HummerDinger a three-ton mall-crawler]] slams into the back of it, while a hatchback would likely get flattened. (It's often joked that safety-conscious parents in the US will refuse to buy their newly-licensed teenage children anything smaller than a Toyota Camry, precisely for this reason.) Finally, Americans are pretty much the world's largest consumer of automobiles, spending much more time in their cars due to suburban sprawl and an inferior rail system to Europe, meaning that their standards for a good daily driver, especially where comfort is concerned, are much higher than those of most Europeans. When you import European compacts to the United States, they become much more expensive, but still use relatively cheap engines and construction.\\\
The end result is a tiny hatchback that may have high gas millage, but strains to go much faster than highway speed (which it's gonna meet a lot more often in the US than in Europe), puts out stunningly noxious emissions for something so small, lacks many of the creature comforts that American drivers are accustomed to, and is a DeathTrap in the event that it gets into a high-speed tangle with the average American truck. This is the reason why, with the exception of Volkswagen, European cars in the United States are almost exclusively either luxury/performance vehicles like Mercedes-Benz, BMW, and Bentley, or niche brands like Mini and Fiat (which, in America, only sells its quirky 500 hatchback and the 124 Spider roadster as opposed to the rest of its European lineup[[note]]Though admittedly, part of this is because other vehicles are [[MarketBasedTitle sold as Chryslers and Dodges]] in the US[[/note]]). The Yugo, for all its [[TheAllegedCar flaws]], was one of the few European microcars that actually met the American emissions and safety standards of the time. The Smart car also took nearly a decade of intensive redesigns and tweaking, on top of some cost-cutting import deals, to even become ''street-legal'' in the US, let alone practical in the American market. The only hatchbacks that do well in the US are 'hot hatches' that also have performance to spare, and even then, they're a niche market that's most popular with urban buyers (who live and drive in conditions closer to those of European cities).
* Convertibles are incredibly impractical. In exchange for having an open roof, you get less storage space, less safety, less gas mileage, less speed, and are easier to break into. On top of all this, they're much more expensive than a standard car.
** They're also structurally weaker than a typical car -- a convertible relies on the strength of its lower chassis to hold it all together, while other cars have a stronger unibody frame that is much better at resisting collisions.
* The ''Hummer'' H1. It's practically a brick on wheels, which is all it has going for it. It comes with a ton of blind spots, no driver space, flashy and useless aesthetics, and trying to tow it will result in the bumper being ripped off. All this for over $100,000.
** The H2 and H3 that replaced it are more practical, but only marginally so. They're still huge, expensive and fuel-inefficient. And don't even look as badass as the H1, so you could even say it's the worst of both worlds: still impractical but not as awesome.
** The [[YanksWithTanks US military]] decided that, instead of scrapping old [=HMMWVs=], they would be sold on the commercial market at auction. Small problem: they were for off-road use ''only''. Several states don't allow military vehicles ''on road or off road'' without modifications to make them legal.
* [[http://magyarbusz.uw.hu/ikarus293.html Ikarus 293]] double articulated bus. While it had a high passenger count, it was too long, slow, and problems with turning making it unable to take corners in Budapest. Only one prototype was made. Later it was sold to Teheran after replacing the engine with a stronger one. Double articulated buses in general have seen some use[[labelnote: example]]Hamburg - which has no light rail - uses double articulated buses as double decker buses would not fit under all bridges and Hamburg has ''a lot'' of bridges.[[/labelnote]], but they are mostly a more expensive and prone to failure way to do what buses towing a trailer, double decker buses or light rail vehicles can do much more reliably. And with both double decker buses and light rail there are benefits in terms of tourism (e.g. London double decker buses) or higher acceptance (many people who'd never take the bus have no problem taking rail based transit as study after study has shown).
* In general, concept cars are this by definition. Meant to be a demonstration of a proof of concept with no real intent to be put into mass production. A good example is the BMW GINA, the fabric car, which is made of spandex and is as durable as your shirt.
* Classic cars. While to an aficionado they look impossibly cool, they rarely get the sort of treatment that'd make them reliable and safe - that is, a complete rebuild and modernization. Mostly they get partial rebuilds to keep them on the road, and modernization is actively discouraged in the vintage market, which prices them higher the more stock they are. Driving a car manufactured with the material science and safety culture of several decades ago on modern, traffic-packed roads is not a good recipe for a stress-free life.
** A special mention goes to vintage sports cars, which in addition to all this don't benefit from the technological advancements that allow your average cheap hot-hatch to soundly beat them on a race track.
** They even lampshade this in ''{{Film/Skyfall}}'': [[Creator/JudiDench Dame Judi Dench's]] M comments quite unfavourably about the ride quality of ''the'' classic car, the [[https://en.wikipedia.org/wiki/Aston_Martin_DB5 Aston Martin DB5]]. (Although being fair, the car is almost comparable to a typical mass-market sedan or coupe even today, is far more powerful than most modern economy cars, and -- laconic British wit notwithstanding -- is still a DB bloody 5.)
* Drifting as a cornering technique. While it makes the person doing it look badass, it actually makes you corner slower. It has been proved that a 600 HP drift car drifting around a track is slower than a 150 HP van going around the same track without drifting. The {{Mythbusters}} also showed the same thing with one car, just driven differently in two different runs, and it did better when not drifting.\\
In the final season of mythbusters, they revisited the drifting vs regular cornering. While the final result is that both "always drift" and "always normal cornering" have more or less the same time, they noticed on certain corners, normal cornering is faster while some are faster when drifting. Long story short, drifting is situational.\\
Additionally, the tires will wear out much more quickly if drifting is performed regularly. This can be a money pit with sports tires so don't unless you have the cash to spare.
* The point of super/sports cars. They look pretty, they're loud, they have a lot of horsepower and can travel pretty darn fast... on a straight road with no bumps whatsoever. Otherwise, [[http://www.youtube.com/watch?v=tFbG-4VWqpA be prepared]] for bumper repairs or scraping bottom. As an extra insult, supercars offer little to no room for even an extra kid, a pet or a small luggage, making this an inversion of BiggerOnTheInside trope. For the budget-minded who wants to get the feel of one, super cars are better experienced in a [[RacingGame video game driving simulator]] with a simulator steering-wheel and controls.\\
To add insult to injury, some countries don't allow registration of vehicles which have opposite steering columns or impose severe usage restrictions. In Australia for example, the steering wheel must be located on the right hand side (RHD) for registration on public roads, unless the vehicle is over 15-30 years old depending on what state you are in. So unless you plan on doing a lot of track days or paying thousands of dollars to convert it to RHD (surprisingly, both of which many people still do), the car will sit in a garage for years before it can even be used on public roads. Even worse are countries such as Singapore, which do not allow the import or registration of LHD vehicles to any citizen ''at all''.\\
Also, due to the impractically high price of the super cars, it is likely to fall victim to being [[TooAwesomeToUse too awesome to drive]], due to fear of being involved in a collision or simply incurring wear and tear with use; these vehicles often stay in owner's garage and are only taken out occasionally due to how costly [[https://en.wikipedia.org/wiki/Depreciation depreciation]] is. A notorious case of this fear being realized is Stefan Erikssen's red Ferrari Enzo (he owned two! the other was black), which was [[http://www.wreckedexotics.com/special/enzo/ wrecked in Malibu]] - a theory on the incident was that the car was doing 200mph when it hit a 1 inch bump at an angle, which would have caused the driver to lose control if he wasn't hanging on tight.\\
This was also a [[StupidCrooks dumb criminal]] moment for Stefan who owed payments on the Enzo to the Bank of Scotland and smuggled this and other cars over seas to evade repossession; to make a long story short, his organized criminal operations awarded him a prison sentence.\\
Furthermore, in a discussion about Ferraris and this trope on the TV show ''Series/{{Castle}}'', the titular millionaire mystery writer points out that no matter how cool they look and how fast they ''can'' go, such cars are ultimately no faster than any other vehicle on the street when they're stuck in rush-hour traffic.
** Exemplified by the Bugatti Veyron. Designed to be the fastest "production" car ever designed, it can go 252 miles an hour. Assuming you can find a straight road long enough to let you do so (you can't, except on test tracks). And assuming you don't run out of gas (it will go through the entire tank in 12 minutes) or have an catastrophic blowout (the tires will let go after fifteen minutes ''when they're brand new'' at top speed). It's also a production car in a very limited sense: only ten were made, and sold with a $1,000,000 price tag. Despite the fact that each one cost Bugatti (aka Volkswagen) $5,000,000 to make ([[TopGear I don't think they have the best accountants]]).\\
When the world speed record for production cars was broken by another car, Bugatti responded with the '''Veyron Supersport''', which can reach speeds of 269 miles an hour, but the tires will give out even faster if you do somehow manage to reach that speed, [[CrackIsCheaper and they're ''$20,000'' a pop]]. Suffice to say, the Veyron is an amazing amalgamation of technical and engineering genius, but ''not at all'' practical for ''anyone''.\\
Due to an engineering oversight, the gears are not even suited to that kind of power. In a lot of them the gears broke down after just over 12,000 miles. Although, if you have the money to buy a car worth a million, you probably don't have that many problems with overhauling the car every once in a while.\\
The Bugatti Veyron isn't even a good track car for the price due to the fact that it is just so heavy. With the Veyron, you get very little bang for your buck as you can honestly drive faster on most racetracks and roads in general with a much lighter and less expensive sports car. For instance, the Lamborghini Huracán, also developed under Volkswagen, costs $320,000 [=USD=] fully equipped. [[https://en.wikipedia.org/wiki/List_of_Top_Gear_test_track_Power_Lap_Times It beat the Veyron on the Series/TopGear test track by 1 second.]] As it turns out, the Huracán even beat the allegedly higher-tier Lamborghini Aventador [=LP700-4=].
** The SSC Ultimate Aero Twin Turbo, the car that unseated the Veyron as the world's fastest production car (then was unseated yet again by the Veyron Super Sport) has ''1,183'' horsepower. Unfortunately it is rear wheel drive, meaning all that power and torque is applied only to the rear, resulting in a car that fishtails in corners at the slightest blip of the throttle. There's a reason the Veyron is all-wheel drive.
** [[http://www.hennesseyperformance.com/ Hennesey Performance]] is also vying to break production car speed records with their purpose-built "Venom GT". The Venom has broken the '''270 MPH mark''', though it isn't an official Guinness World Record because the vehicle hasn't met the criteria that the Bugatti Veyron had to meet, namely 30 cars must be produced and the car must complete two top-speed runs which are then averaged. Hennesey Performance also specializes in outfitting common vehicles with obscene engine power, that lets you greatly exceed the speed-limits on most roads if you feel like risking time in the slammer. DontTryThisAtHome.\\
[[http://www.hennesseyperformance.com/vehicles/hennessey/venom-f5/ Hennesey]] is now developing the next generation of their Venom, the Venom F5. The company is advertising 290 MPH as the goal for the vehicle's top speed. The car will see limited production, with 30 units estimated, so it will likely be too rare for customers to want to break it in.
** Also, some supercars (e.g. Bugatti Veyron, Ferrari Enzo) are only built with the steering wheel on the left hand side (LHD) unlike most other vehicles, which are built in both configurations. This can make driving the vehicle in a country which uses the opposite standard very difficult.
** [[https://www.youtube.com/watch?v=PNJ5fARN3EM Modified Super Cars]] are even more impractical compared with their unmodified counterparts. On top of the costs form the original car, more cost is added from the engine tuning and the additional performance parts. This engine tuning will typically shorten the lifespan of the engine due to extra stress, and likely also reduce fuel efficiency. The added performance can legally only be used on a race track, unless you have an autobahn nearby to take the vehicle to its top speed.
** Likewise, supercars in police forces. They look like they're designed to chase criminals at high speeds, but most criminals don't themselves use supercars in the first place, so you can perfectly effectively chase them in your average souped-up police cruiser - the maintenance and parts for which are a fraction of the cost of what the city would have to pay to keep that Lambo on the road. As for the occasional criminals who actually do use very fast cars, cameras and helicopters are much safer than initiating a 300 km/h chase on busy highways, even if your department owns a car capable of doing so. Supercars ''can actually'' be drafted into a police force if local laws allow illegal, confiscated property or personal vehicles to be used in police operations.\\
One practical use for the supercars, particularly all-wheel-drive ones, is rushing organs for transplant from donor to recipient when having them in the same facility or using aircraft isn't practical, which is not as infrequent as you'd think.
** Motorcycles with colossal engines in the frame; generally, it's overkill to bolt a high-liter engine like a V8 into a bike [[https://en.wikipedia.org/wiki/Boss_Hoss_Cycles such as with the Boss Hoss Cycles]], and with an engine that heavy, the bike isn't as good at taking the corners, especially with only two wheels of grip. Admittedly, it sounds like huge thrill to take one for a ride in a straight line, but they are quite expensive brand-new, easily approaching the price of a respectable sports car.
* ''[[https://www.youtube.com/watch?v=u_8VueuEtH8 Luxury Cars]]'' tend to suffer from this trope, due to their prime technologies. (This high-technology is also causing trouble with common cars; with the addition of more computerized parts, some people and mechanics may express concern over their lack of durability compared with their low-tech equivalents, as well as fears about DarthWiki/IdiotProgramming.) Many luxury cars have specialized parts such as [[https://www.youtube.com/watch?v=pJzoyCPiAjg high-tech shocks]] to improve the quality of the ride. Sadly, many luxury vehicles are made in small quantities, so the only part builder to buy from may be the vehicle's manufacturer, raising supply costs tremendously. This is why buying a used high-luxury car may look like a good deal, until it is time to seek out a repair-shop and learn what you will be paying on top of that. Buy a luxury car only if you can afford the [[CrackIsCheaper cost of ownership]], or you'll kiss a large percentage of your money goodbye.
* Small nuclear powered vehicles. They could last very long periods of time without any refueling and would emit no carbon dioxide, but every crash or accident would be a potential radiological emergency. It is safer and cheaper to use a stationary reactor to make synthetic gasoline or hydrogen, then use that to power a car or a plane.
** [[http://en.wikipedia.org/wiki/Ford_Nucleon Ford Nucleon]], a nuclear powered car. Over 5000 miles between refuelings, but imagine the mess that would result if you let notorious speeders drive it.
** The smallest nuclear-powered vehicles ever actually tried, were ''strategic bombers'' made by the US and USSR in TheSixties. While both indeed flew with active reactors, none actually was ''powered'' by it (the reactors were idling, and the flights were more to test the shielding). As soon as practical [=ICBMs=] arrived, both projects were dropped.
* [[http://en.wikipedia.org/wiki/Concorde Concorde]]. Supersonic airliner which was cutting-edge at its time and many considered it to be the future of commercial flight. The problem was that it guzzled huge amounts of fuel and its aerodynamic body had very limited passenger space, which meant carrying small number of people at high cost, so no wonder Concordes went out of service by 2000's. And there are very few airports that serve as Concorde terminals; you'll ever see a Concorde, let alone fly in one, if you're making a trans-Atlantic flight. Famously, a NASA engineer once said that "putting a man on the moon was easy compared with getting Concorde to work".
** Besides, the Concorde has been retired for quite a while now, and supersonic airliners are unlikely to return. Going past the sound barrier is too inefficient for civilian flight, period. Also, these days, if you need a meeting with your partners in NY, just set up a webcam. It wasn't retired because it was too fast - in the digital age, it was too slow.
** Part of what helped kill it was also the US government over-regulating to prevent it getting into their airspace (farmers even argued that the sonic boom would ''knock over their cows''). Why did they do this? Because they were spiteful at the failure of their ''own'' project, the Boeing 2707, which would have been even more AwesomeButImpractical, at Mach 3. Of course, that big crash couldn't have helped, either.
*** Those same rules apply to American military jets, of course. Among various noise complaints, sonic booms can also shatter windows if done at low enough altitudes, as once infamously happened during a flyover at an Air Force Academy graduation. Noise problems aside, most planes ''capable'' of supersonic flight tend to lose all semblance of fuel economy at those speeds, making that capability an example in and of itself except for some specific circumstances.
** The Concorde was conceived in a period when talk of the "space age" was all the buzz and optimism about the future was rampant. It hit the market shortly after the first oil crisis taught everyone that unlimited cheap oil was a fantasy. Only two airlines ever bought it (Air France and British Airways, which were at that time both basically state-run) and the Concorde never saw any widespread use outside its London/Paris-New York route. While Air France and British Airways made a small net profit all things told, the development costs never got even close to being paid back. Arguably this failure of a combined Anglo-French effort helped bring about the consolidation of the airplane market into the two giants Airbus and Boeing with other companies like Embraer or Bombardier relegated to small jets at best.
** The Soviet Union developed the Tupolev Tu-144 which was remarkably similar to the Concorde[[note]]Both sides accused the other of industrial espionage and the Western press took to calling the Tu-144 "Concordski", but nothing was ever conclusively proven.[[/note]]. Needless to say, it was a spectacular failure that was wracked by many unresolved problems such as inefficiency and poor quality materials and components. One can't help but wonder if this was an ill omen for the Concorde's future.
* Any and all turbine-powered road vehicles intended for civilian use.
** Those that use turboshafts (such as the [[http://en.wikipedia.org/wiki/MTT_Turbine_Superbike Y2K motorcycle]] or [[http://youtu.be/wQM_TyyRye4 this minivan]]) have massive turbo-lag issues, guzzle fuel at a prodigious rate and are eye-wateringly expensive. And while they generate a lot of raw horsepower, internal-combustion vehicles built for high performance can almost always do the same or even better at a vastly inferior price.
** Those that use turbofans or turbojets (such as [[http://www.ronpatrickstuff.com/ this jet Beetle]]) run into the basic problem that relying on pure thrust is not very efficient on road vehicles. They eventually get to rather prodigious speeds, but acceleration tends to be slow and the noise extreme, and this is on top of the same problems turboshaft-powered vehicles suffer. The result is certainly very exciting, but very unlikely to do better than a vehicle with a powerful tuned internal-combustion engine in it.
** Even military turbine-powered road vehicles have dubious practicality. The only two nations to field a fully turbine-powered vehicle were the US and USSR (notice the pattern?), and the Soviets canned their turbine-powered tank, the T-80, as soon as The GreatPoliticsMessUp happened, because [[WhyWeReBummedCommunismFell they couldn't pour money into their fuel tanks anymore]]: one T-80, including building, maintenance and fuel expenditure, was equivalent to ''three'' T-72 or T-90. A common joke has it that the Americans are only keeping a turbine-powered tank because of their habit to solve any problem by drowning it in money.
* Flying cars. A staple of science fiction, sure, but consider the drawbacks when it comes to safety, energy efficiency, the fact it's difficult to take off and land vertically in a very stable manner, etc. Most real life attempts at building one also require a pilot's license which is rather more difficult to obtain than a standard driver's license. In other words, just go to flight school and learn to fly a small airplane. In fact, all existing "flying cars" are actually less of a flying car, and more of a drivable airplane.
* Self-driving cars, as they currently stand. On paper, an automated personal vehicle means you can relax and not have to worry about controlling the car, leaving your hands--and your whole mind and body, for that matter--to do things like study, conduct work-related activities, eat, and use telecommunication without some sort of hands-free device; to say nothing about the potential usefulness for those who have disabilities that prevent them from driving. But automated cars still have a long way to go before they can be safely used on a mass scale, with ArtificialStupidity being a major concern; navigational errors can result in missed turns at best and fatal accidents at worst.
** At this point self-driving car technology has evolved to the point where they're extremely good at following traffic laws. In fact, sometimes they're TOO good, causing accidents because other drivers weren't driving properly and the smart car failed to react accordingly. Not to mention the ethical debate of whether nor not a self-driving car should be allowed to let its owner driver crash if doing so would prevent a much larger accident, as well as the legal complications about who's at fault for such an event.
* In many parts of the world cars can be that. Sure, they can take you (almost) everywhere at top speed well above 100 km/h, but chances are, most of the time they will not move at all, being parked. And when they move, it is most likely for commuting in suburban or city roads where a car cannot let its speed advantage come into play due to congestion. Many cities were not built for cars at all and parts of the inner city may even be off limits to cars entirely. Add to that the fact that gas, insurance and all the other costs owning a car causes tend to get higher every year and it becomes understandable why BoringButPractical solutions like bicycles or light rail are gaining ground among young people.
* Automatic gearboxes. Sure, not having to shift yourself is really comfortable, but automatics are less reliable, harder to fix, more expensive and don't give you too much control over what gear should the car be in, And if you live outside of the 1st World, good luck finding a repair shop that will repair an automatic gearbox at a reasonable price. The exception to this rule can be jobs that require free hands, such as a police officer. If cops are in a vehicle chase, the need to operate the radio to communicate with dispatch is important.
** Whether you believe this to be the case really depends on [[LoveItOrHateIt where you live in the world]]. While only about 20% of the vehicles on the road in Europe and Japan have automatic transmissions, ''97%'' of North American vehicles are, with the majority of available models not even having an option for a manual gearbox. Manual transmissions, outside of some very specialized situations or applications, are on their way to extinction in the United States and Canada as most drivers consider the automatic BoringButPractical. If you drive in a hilly city with frequent stops on inclines, then the convenience can truly shine by eliminating the danger of rolling backward.
* Wankel Rotary Engines have intriguing advantages. They weigh less than a piston engine for a given power output, are much more compact, can easily rev up to an exciting amount of revolutions per minute (The Mazda RX-8 red-lines at 9000 RPM, limited by the durability of the transmission). They are also very smooth with almost no negative vibrations.\\
Sadly, Wankel engines (Mazda RX-8 and before) have a history of significant drawbacks that made them unattractive for most auto makers to develop; only Mazda has a history of significant investment in the design. Wankels tend to suffer from inefficient combustion, leading to lousy fuel economy for such a small engine, as well as emission troubles. The Mazda-designs also burn a small dose of motor oil by design, to prevent the apex seals from wearing quickly.\\
With emission regulations becoming stricter over time, Mazda Wankel research tends to be low priority. [[http://www.youtube.com/watch?v=v3uGJGzUYCI Engineering Explained]] on [[Website/YouTube YouTube]] has an explanation of the drawbacks. However, their use as a generator for a hybrid-electric car is being considered, where the rotor can be kept at fixed-optimum r.p.m. for maximum efficiency; this setup makes the engine solely used to generate charge for the batteries, much like diesel-generators on most modern railroad trains, known as "Diesel-electric" trains.

* There are a lot of devices, often (but not always) sold in infomercials, marketed on the idea of "How '''awesome''' would it be to make (insert popular restaurant food or drink item here) in your '''own home'''?!" Five months later you will have only used it once or twice after you got it, promise to use it again at a party and forget about it being there until the next time you clean out the cabinet under the sink. That and quite a few of them do not work as advertised anyway. And even those that do perform their job as intended are often so cumbersome to clean that the usage time plus the cleaning time is more than you'd spend doing the job by hand.
* The Slicer-Dicer. For every good review you'll find online there'll be several that complain about the device breaking under the strain and several more that complain of bad design, with the thing failing to do what it's supposed to in anything like the efficient manner shown in infomercials.
* The Magic Bullet blender. While in principle a decent idea - turn the concept of the blender upside down so you blend directly into sealable cups - the cups themselves are fairly small, limiting the amount of food you can process, and more importantly the motor is liable to overheat and break.
** On the other hand, if you need to prepare only small amounts of food, such as hot chocolate, whipped cream, various sauces, smoothies, milkshakes or dips, or if you live in a small household, the Magic Bullet is a true win. Usually ten swift less-than-second pushes are enough to prepare the food.
* The Miracle Blade knives. Billed as super-sharp and all-but-undullable, anyone with any knowledge of metalworking at all will tell you that's impossible. The sharper you make a blade the quicker it'll get dull; the Miracle Blades get around this by having a serrated edge that'll make them cut with ''some'' usability even when the actual sharpness has long gone to hell, but it's effectively cheating, and the quality of the cut will still plummet as they are used.
* Speaking of knives: ceramic ones aren't quite the revolutionary product they're advertised as. While it's generally true that a ceramic knife will hold a scarily sharp edge way after a comparable metal one will be so dull as to be useless, a few passes over a sharpening tool or stone every now and then will keep the latter sharp for a long time (almost indefinitely if you also hone them regularly, greatly reducing the need for sharpening). Ceramic knives, on the other hand, are expensive disposables: their blades are far more delicate, so instead of getting dull they chip and crack (losing efficacy as they go) until enough structural integrity is lost that the blade snaps. This is a rarely seen failure mode, though, because most users will drop them and shatter the blade long before then.
* The [[http://www.bialettishop.com/MukkaMain.htm Bialetti Mukka]], intended to make a nice foamy cappuccino without the expense and complication of an electric espresso machine equipped with a milk frother. Instead it makes an excessively foamy white coffee that tastes rather differently than a true cappuccino. Which might not actually be unpleasant, depending on your tastes, but the Mukka is also fiddly to prepare, harder to clean than an ordinary moka pot and rather temperamental as the valve design is imperfect: occasionally it provides insufficient pressure for no apparent reason, resulting in an unsatisfactory brew.
* Any gadget ever invented to quicken the process of peeling vegetables is either inefficient (leaving bits of skin that you have to inspect for and manually remove with a normal peeler anyway) or incredibly messy (save time in peeling, waste it again in washing the gadget). A good peeler and a fast hand are still the fastest way to get rid of the skin on potatoes, carrots and what have you.
* The Rollie Eggmaster vertical grill, a compact travel appliance to make small portions of food for a rapid lunch break on the go - in theory. In practice, compare the yummy, colourful food it makes [[https://www.youtube.com/watch?v=1XILbEZlS0U in the infomercial]] to the [[http://www.thepizzle.net/the-rollie-eggmaster-is-the-best-dumbest-cooking-device-ever-invented/ actual food it, uh, "shits out"]] (that's not gratuitously added vulgarity, by the way - that's from ''the review text''), just in case you thought that this was a one off here is [[https://www.theguardian.com/lifeandstyle/2015/jul/15/kitchen-gadgets-review-egg-master-horrifying-unholy-affair the review]] from the [[UsefulNotes/BritishNewspapers Guardian]]. Anyone who needs a quick meal and isn't too picky about quality will likely just eat some frozen microwave meal or fast food.
* Shopping at high-end kitchen gadget shops can be this, due to the severe mark-up in prices that can occur. Often, you can find the same or similar tools and appliances at discount department stores and internet retailers for greatly reduced cost, and the build quality need not be worse.
* [[http://www.youtube.com/watch?v=Ag0NtfZRTvg It is possible to turn a can of sweetened condensed milk into a substance similar to caramel by boiling an unopened can in water for 3 hours]]. However, when one considers the gas or electric cost of running a stove for 3 hours (even if it's a wood stove, you still need constant fuel), plus the water needed, plus the cost of a can of sweetened condensed milk (which isn't even available in many countries), it is far FAR cheaper to either buy a jar of caramel, or to make it properly with melted brown sugar and butter.
** Granted, if you don't mind waiting longer, you can do this with a crock pot (removing the label first), and once done the finished product has a frankly absurd refrigeration life. A single can lasts for months, and can even be stored in the original can without complications.
** Thankfully, this special, creamy type of caramel (often called "dulce de leche") can now be found in many grocery stores.
** You can also boil an unopened can of sweetened milk inside a pressure cooker. Takes around 30 to 45 minutes and it's just as good as the original.
** Frankly speaking, not a lot of people does this now, when this sort of creamy caramel is widely available commercially, but back in the mid-20th century it often ''wasn't'', even in the areas where it is popular (Latin America and Eastern Europe), so the only way to get it was, you guess right, to boil a can of condensed milk.[[note]]And even then, the most popular commercial technology is… ''to boil cans of condensed milk'', though they usually use pressure cookers in a factory.[[/note]] And the cost of making a batch is actually not that greater than the cost of a pot of soup — after all, to get a good meat broth you need to boil it for the same 2-3 hours.
* Lots of gourmet cooking techniques and dishes qualify, at least for most amateur home cooks.
** Special mention goes to ''gold foil'', which is exactly what it sounds like - a very thin sheet of reasonably pure gold that you put onto food and then ''eat''. While it is, somewhat surprisingly, safe to eat, the body will simply pass it through, and it has no discernible taste - basically it's a way for the excessively rich to garnish their food with bling while giving the finger to anyone for whom hunger is a daily problem.
** Similarly to gold foil, but far more common are cheap, silver dots. Like the foil, these are meant to be decorations but at a much more reasonable cost (generally only a few dollars a pound) and look pretty good on home-made confectionery. However they taste absolutely meh; they're basically condensed sugar dots with a coat of edible silver paint over them. Not to mention if you present this to people who are not familiar with them at all, they might think your food is inedible to boot.

[[folder:Electronics & Programming]]
* Transparent displays. A staple of sci-fi movies and TV series. They've been in existence since the early 2000's but never caught due to a shifting background being distracting.
* Most novelty mice. Car-shaped mice might look good if you're using them in a showroom or something, but they're all an ergonomic disaster.
** [[http://blstb.msn.com/i/5C/CDD927B1EF33E77109D75255C5DB.jpg 8-bit]] [[SuperMarioBros Mario]] [[http://craphound.com/images/mariogoombamice.jpg computer mice]]. They're nifty and look nice, but they're also large, clunky, and uncomfortable.
** Specialised gaming mice can have up to 20 buttons on one side, including the standard mouse buttons, to control with your thumb. For comparison, an X-box controller has 15 buttons for both hands.
** Apple ended up making this mistake with the Apple USB Mouse M4848, commonly referred to as the "hockey puck" due to its circular design, proving to be incredibly uncomfortable after prolonged use and quickly became hated by users. The company discontinued it after two years.
* Dream [=PCs=], often with thousands of dollars' of processors, graphics cards, and liquid cooling system, and have the specs that could conquer any game currently on the market.
** The practical problem with expensive hardware is that you get next-gen performance on current-gen hardware. Your rig will become ''outdated'' long before it becomes underpowered. Anyone who bought a top end single core CPU or [=DX9=] video card probably ended up replacing it quickly, not because it was too slow but because it was not a multicore CPU or [=DX10=] card. This has become less of an issue in more recent years; five year old computers can still regularly play games, whereas back in the 1990s and early 2000s that was unthinkable. The biggest problem tends to be that you end up overpaying for the extra performance beyond a certain point.\\
Emulation solves that problem in general however, as a matter of fact a PC can emulate any platform to run virtually anything within the PC's resource capability (including console games, which are developed and tested in a PC to start with) provided they have the necessary detail that has to be emulated (and naturally console makers make it a point to safeguard their console platform from it).
** [=3dFX=] was a graphics company popular in TheNineties. Their magnum opus was [[http://en.wikipedia.org/wiki/Voodoo_5 The Voodoo 5 6000]]. A card with four separate processors and ''an external power supply''. The card drew too much power for the motherboard to provide by itself - far from an uncommon problem in the years to come, but now we just run a wire from the main power supply, while back then it was feared that they wouldn't be powerful and reliable enough.\\
Despite that, the Voodoo 5 did not support hardware transform and lighting (depending on the main CPU to do it). The Radeon and Geforce were released BEFORE the Voodoo 5 was finished, did support those, and pretty much hammered the Voodoo 5 into the ground in performance, at a fraction of the cost. 3dfx ended up going out of business and being bought by Nvidia.
** Enthusiast video cards often fall into this, offering high-end video rendering for the current generation, but easily exceeding $500. It is quite feasible to get by in gaming with a [[SimpleYetAwesome mid-range video card]] for the current generation, with most games on the market, or you can [[BoringButPractical dial-down the visuals]] in many games to make up the difference. Also, when the next generation of video cards roll around, the enhancements on the previous high-end models may be applied to the newer, less costly models.\\
Even more expensive is running up to [[UpToEleven four video cards]] like with Nvidia SLI & AMD Crossfire. Sure, you can harness immense graphical processing power, but when the video cards can't handle the latest games, you now have to [[CrackIsCheaper replace 2-4 video cards]] if you want to continue reaping the benefits. The expense of the reqired motherboard is also increased, and the main CPU will become obsolete someday too. Using a multi-core graphics card for a reasonable expense can provide a similar benefit for significant money savings.
** Cutting-edge gaming laptops allow desktop performance for the games of that laptop's era, but the price of one can easily exceed $1,000 USD, a high price to pay if theft or damage occurs. Laptops also suffer from inflexibility for upgrades, and usually can not have the video upgraded, leaving an insurmountable bottle-neck that can obsolete the machine for gaming, prematurely.\\
A miniature desktop box can be a much more cost effective, allowing a degree of portability (provided the destination has peripherals set up), and you can still upgrade the video card when needed. Homebrew projects exist that can install a desktop machine and monitor into a briefcase for a desktop on the go, and these ''can'' be upgraded with ease, right down to the motherboard.
* The iPhone 4's antenna, which is that stainless steel banding built into the casing of the device, was described as "really cool engineering" by Steve Jobs. However, [[http://news.bbc.co.uk/2/hi/technology/8761240.stm the iPhone doesn't work very well as a "phone" when you hold it, leading to dropped calls]].
* Buying arcade boards and machines, especially when a home port of the game in question exists.
* [[http://www.youtube.com/watch?v=Z86V_ICUCD4 The Most Useless Machine Ever]], a device whose sole purpose, once turned on, is to turn itself off.
** Needless to say, it spawned a race to design machines that are even more awesome while retaining the utter uselessness of the original. Cue the [[https://www.youtube.com/watch?v=Djc8FPHs45o advanced edition]]…
* [[http://en.wikipedia.org/wiki/Esoteric_programming_language Esoteric programming languages]]. For example, brainfuck has only 8 commands yet is Turing-complete, and compilers for it are ridiculously small. There is also LOLCODE, where many commands are replaced with internet memes. However, these languages are really not practical for any serious programming.
** Some of them are designed for hypercomputers, which means that it's physically impossible to build a computer that can run them in this universe.
** While we are at this, it takes actually exactly ''one'' instruction to make a Turing-complete universal computer. Of course, such computers are no more practical than the aforementioned esoteric programming languages, and are their thought experiment counterparts. They are notoriously tricky to program for (and it's with the most straightforward subtract-and-jump-if-(not)-equal instruction), and their efficiency is atrocious.
* For a long time, computer programmers considered interpreted programming languages to be this. These languages are easy to code for, but until fast computers with lots of memory became commonplace, they were resource hogs. Now that machines can run interpreters without a huge performance hit, assembly and C are seen as awesome but impractical for making a programmer have to define everything manually and leading to major security holes such as [[https://en.wikipedia.org/wiki/Heartbleed Heartbleed]]. C's use of pointers for manual memory management is a huge source of bugs in many programs for a small increase in performance. Systems programmers are moving to Go and Rust because, while being compiled languages like C, they manage memory automatically while offering good performance.
* There are lots of cool website designs that look awesome, but load slowly and are hard to navigate.
* Wi-Fi connected "smart" light bulbs have apps which can imitate a thunderstorm or fireworks, by simply flashing the light bulb. It is very cool to get the "effect" of a thunderstorm or fireworks in your own home but consider the fact you turn on a light to see in the dark, and these apps flash the bulbs intermittently.
* The Nintendo3DS 3D feature. It may look nice but there's two problems: (1) If you move the screen even a little, a distracting flaw appears. (2) Using it continuously drains the battery in three hours. Nintendo may have fixed the screen problem by [[http://en.wikipedia.org/wiki/New_Nintendo_3DS adding an eye-tracking camera feature]], but most people still prefer to play their games in standard vision.
** Even the new system has problems. It has a wireless transfer program that works with your computer so you can move video/audio/pictures to/from it without removing the Micro SD Card. The flaw? Not only does it take ages to do so but some of the files might not transfer properly. You're better off unscrewing the back of the system, removing the Micro SD Card, and inserting it manually into your computer for file transfer. Not to mention the fact that they could have just as easily done what the original 3DS did and made it possible to swap out Micro SD Cards without physically disassembling the system.
* The Dvorak keyboard layout. It's supposed to be more efficient than the standard QWERTY keyboard and cut down on repetitive motion strain (unproven). Also every major operating system supports it in software. Unfortunately the typical Dvorak keyboard runs well over $100 and no IT department will appreciate you gluing new letters onto your keyboard.
** Many keyboards have pop-off/pop-on keycaps, so you could move them around, reversibly. Or learn to touch-type in Dvorak and don't even look at the keys. These both require going under the hood and remapping the keyboard, of course. (Some people's skin gradually wears the lettering off computer keys, so they can touch-type, replace keyboards regularly, or glue on new labels.)
** Additionally, note that the Dvorak keyboard is based on a myth; its creators believed that the QWERTY keyboard was created to slow down typists. This, at least, is well-documented as being untrue. (The arrangement has to do with the exact mechanics of the inside of a typewriter and the way certain bars tended to jam when struck together, not with any deliberate attempt to slow down typists.)
** [[DamnYouMuscleMemory The major problem is that you have to completely re-learn touch typing]]. While switching may lead to faster typing in the long run (as mentioned, there's no hard evidence either way), it will definitely slow you down in the short term. It also makes it incredibly inconvenient to use anyone else's computer (or a public computer) and, conversely, inconvenient for anyone else to use yours.
* TV sets with [[http://en.wikipedia.org/wiki/4K_resolution 4k resolution]]. 4k is basically twice the horizontal ''and'' vertical resolution of HDTV, and is regularly used in digital cinema. So it's a TV with the resolution of a movie theater! The first such models are 84" diagonal, and start at about $20k. While there already are a handful of 4k videos posted on YouTube, nothing is currently broadcast at this resolution, and won't be without another major upgrade to TV equipment. It is doubtful that such an expense would ever be justified, as most people don't seem to really notice a difference between the 1080p resolution of Blu-ray and upconverted DVD.
** But if that's not enough for you, try the format-after-next [[http://en.wikipedia.org/wiki/UHDV 8k UHDTV]] (ultra high-definition television) resolution. Yes, that doubles the x and y resolution of 4k. At 7680x4320, that approaches the resolution of friggin' IMAX film! And don't even get started with the associated audio format of [[http://en.wikipedia.org/wiki/22.2_surround_sound 22.2 surround sound]] ({{exactly what it says on the tin}} -- 22 speakers and 2 subwoofers.) Just a little overkill for watching the news, no?.
** And, as of 2013, games are starting to be developed with 4k resolution. While it gives PC elitists bragging rights over the [=PS4=] and X-Box One not supporting it, the market saturation needed for it to be anything more than a talking point does not yet exist for the above reasons. You'll also need an extremely powerful PC to be able to run a game at 4K, unless you like your framerates measured in seconds per frame.
*** A bit less so in 2014, with [[http://www.amazon.com/dp/B00I0H9T5C/ 4K monitors going for as low as 600]].
** The fundamental problem is that the primary component of "quality" of a picture is pixel ''density'', not ''number''. An 84" 4k monitor has about the same number of pixels per inch as a 42" HD monitor. And it turns out that the human eye has a severe law of diminishing returns for moving picture quality. While a human can easily tell the difference between a picture printed on a 300dpi printer and one on a 1200dpi printer, it can't when comparing a 300dpi monitor vs a 600dpi monitor. 4k resolution on a 20" monitor is about the best a human eye can distinguish.
** Even better, 4k displays for ''smartphones'' are in the works. Nice, you have the resolution of a next-generation TV in your pocket...but given that the individual pixels on a 1080p smartphone are already barely discernable, having four times the pixel density on a phone is overkill.
* Digital Projectors in comparison to [=TVs=]. For around 500 USD you can get a projector able to display a 1080p image at 120'', but the room has to be long enough, there can't be too much light seeping in, the light from the projector can't be blocked (can be solved by attaching the projector into the wall/roof), you need a screen attached to the wall for decent colors and occasionally you need to replace the bulb. In other words, you need to practically build your living room around the projector to get the best results out of it. [=TVs=] just need to be plugged in.
* When buying a 3D [=TV=] you have to ask yourself which compromise you dislike least for proper 3D display. Active Shutter glasses display the content in full resolution (by displaying the left and right images intermittently) but require bulky electronic glasses (blacking out the relevant eye) that are expensive, uncomfortable (both due to the weight of the glasses and the eyestrain that some people experience with them) and need to be synced with the TV. Passive 3D doesn't require electric glasses but is displayed by showing the left and right images on different lines of pixels, effectively halving the resolution. Both also compromise color contrast for the 3D effect, as the glasses darken the image.
* [[WhatAreRecords Vinyl records]], at least in modern times. They subjectively have better sound quality than digital files, and there's just something [[RuleOfCool inherently cool]] about them, but they're large, inconvenient, and ripping them to play on your MP3 player or game console requires somehow hooking up the turntable output to your computer's analog input, or having a [[http://www.amazon.com/ION-Profile-LP-Vinyl-to-MP3-Turntable/dp/B0029QRA1U/ref=sr_1_1?ie=UTF8&qid=1333314049&sr=8-1 special vinyl-to-mp3 turntables]] and recording it as it plays. Record companies seem to recognize this, with many of them offering digital download coupons with new vinyl releases.
** Except the ''better sound'' of vinyl records is caused by the one particular technique which is regrettably abused in the modern ''CD'' mastering: a dynamic range equalization. [[LoudnessWar It artificially pulls up the volume of the quieter sounds and muffles the louder ones]], often across the entire spectrum, so that the overall record might be more even in intensity.[[note]]and, as the producers often hope, perceived as a louder one, as this is commonly thought to be more attractive for the listener[[/note]] Unfortunately, the overindulgence may (and, sadly, too often, does) lead to the record becoming an unlistenable mess, with every detail drowning in an impenetrable wall of sound. Vinyl records have much lower dynamic range than [=CDs=], and don't lend itself to this technique: in a too loud sound the needle will be simply thrown out of the groove. That's why the records usually aren't equalized for the vinyl medium, which leads to the crispier, more detailed sound.
** However, the other thing about [=CDs=] is that they are pre-equalised - they come with a defined bass and treble level whatever you play them on. On a vinyl record, you are amplifying an unequalised signal yourself, so you can adjust the bass and treble settings before it reaches the speakers. The warmth of a vinyl record is usually caused by low level hum that is endemic to the analog medium, that's why digital recordings often sound 'cold' by comparison.
*** The whole 'needle jumping out of the groove' thing is somewhat of a myth, as modern vinyl uses 180 gram records which have deeper grooves and can take higher volumes. Many recent examples have used almost exactly the same mastering as the CD, sometimes taken directly from the [=CDs=] (in the case of bootlegs).
*** Of course one further thing is that when pre-equalizing [=CDs=], the mastering engineers often make questionable choices, such as cutting out the bass to make the music sound 'brighter'. Many audiophiles like vinyl precisely because they have more control over how it sounds.
* "DVD quality" audio, which is spec'd at 24-bits per sample at rate of 192KHz. Compared to the CD which is 16-bits per sample at a rate of 44.1KHz. If you compared the audio signal of DVD quality vs. CD quality audio, DVD quality would look very much like [[http://static.ddmcdn.com/gif/dvd-audio.gif a perfect sine wave]] in digital form. Unfortunately, due to the limitations of the human ear, most people can't tell the difference and the few that do probably have to seriously focus. Not to mention DVD audio takes up roughly ''6.5 times the space'' compared to uncompressed CD audio.
* [[http://www.dannychoo.com/post/en/1630/Japan+Bike+Storage.html This Japanese bike storing machine]] may qualify; it's neat and saves some surface space, but it only stores or produces one bike at a time (making it inconvenient whenever several people want to get or store bikes all at once), it only works for bikes that fit certain specifications, and it also inevitably requires power and maintenance...all unlike, say, a metal bar.
** On the other hand consider as well that to Japan, free space on the surface is a very rare commodity on urban areas if there is any at all. The device similar to their car storage carousel is designed partially to help mitigate the fact that there is simply no room left in Japan cities for storage of the transportation vehicle in the normal manner. The option left are to dig down but having a full sized underground storage area like an underground parking lot also takes a lot of space underground (and that's also in shortage) so it becomes imperative to them to minimize the space consumed at all cost.
** In fact, Japanese cities themselves. It kind of defies imagination to find that the population almost the size of a Russian one willingly confines itself on a barely 30% of the whole suitable land. It is actually very few large cities outside of the Pacific Industrial Belt that stretches from Hakodate to Kitakyushu, and the Sea of Japan cost is in fact very sparsely populated -- you can drive for hours and not see anything except the actual wilderness and some token farmland.
* Certain vintage electromechanical keyboard instruments, such as the Hammond organ and the Mellotron. They sound great, but their intricate mechanisms make them a nightmare to take on tour, as many ProgressiveRock bands found out the hard way. This is why many keyboardists wanting retro sounds use sampled versions on modern digital synths or software synthesizers, which stand up to the rigors of touring much better, with physical instruments largely relegated to studio work. The original analog synths, such as the Minimoog, are also temperamental, often going out of tune easily. Lots of musicians prefer digital recreations for the same reason.
* UsefulNotes/LaserDisc. Sure, it had better quality than [[UsefulNotes/{{VCR}} VHS]], but the discs were expensive and most rental stores didn't stock them, while they had shelves and shelves of VHS tapes. Plus, the discs were huge, the size of an LP. Watching a full-length movie required flipping discs. The format was limited to deep-pocketed film buffs and industrial uses, though [[GermansLoveDavidHasselhoff it was popular in Japan]]. UsefulNotes/{{DVD}}s came along in the late '90s and offered all of the advantages of [=LaserDisc=], including advanced picture and sound while being much cheaper and the size of a CompactDisc.
** Same goes double for UsefulNotes/{{CED}}, AKA RCA [[http://en.wikipedia.org/wiki/Capacitance_Electronic_Disc SelectaVision]]. Never heard of it? It was actually an ''analog'' video disc similar to an LP, only using a capacitive pickup instead of a vibrating needle. The disks were permanently encased in sheaths reminiscent of a 3.5 inch floppy the size of an LP jacket and tended to wear out quickly... like after the second viewing. Not a big success.
* 1080p video. [[Franchise/SpiderMan With great resolution comes great bandwidth requirements]]. No broadcasters currently use 1080p, opting for 1080i or 720p instead. 1080p is mostly relegated to satellite pay per view movies, UsefulNotes/BluRay and streaming video. Even streaming falls into this problem. Like to watch lots of 1080p movies and TV shows on Creator/{{Netflix}}? Hope you don't have any bandwidth caps, especially in America, Canada and Australia!
** If you want to watch a 1080p video on an iPhone, the first (and currently only) one that has a screen resolution high enough to display it without fudging things is the 6 Plus. A few years ago a flatscreen LCD computer monitor capable of that resolution would cost several hundred dollars and require an extremely expensive graphics card.
* As with collecting arcade boards mentioned above, collecting classic computers and game consoles can fall into this, with the need for storage space, power, TV/monitor connection and aging/failing hardware with few options for repair for someone who isn't a GadgeteerGenius. That's why emulation is so popular on modern systems.
* Running emulators and ports on improbable devices, such as ''VideoGame/{{Doom}}'' [[http://www.youtube.com/watch?v=ZvGO8vxrKDE on a printer]] and ''VideoGame/{{Tetris}}'' [[http://www.youtube.com/watch?v=IAIPUGO1iko on a hi-rise building]]. Though they're demonstrations of clever programming and hacking skills, they're obviously not ways that you want to regularly play your games.
* Earbuds may be convenient for travel and workout, but they are lacking in power and quality compared to more full-sized headphones. Additionally, audiophile-grade earbuds, including in-ear monitors, tend to be several times more expensive than on- and over-ear headphones of the same degree of quality due to having to pack the technology into much smaller spaces.
* High-quality cassette formulations, such as chromium dioxide and cobalt, offered superb audio quality rivaling reel-to-reel tape, but since most people only had cassette players that could only handle Type I or "Normal bias" tapes, it was almost impossible to exchange recordings made on the high-end tapes with anybody else. Prerecorded tapes with these formulations were only offered by small boutique labels catering to audiophiles.

* "Cutting-edge-of-fashion", ''haute couture'', designer outfits that might look "fabulous" at the exclusive show in Milan, but would be extremely impractical (if not awkward or dangerous) to wear anywhere else. A morning talk show host once did a short on this, where she wore a runway piece to the supermarket to gauge people's reactions, which mostly ranged from "WTF?" to "The jacket is ''kinda'' cute but..."
** Just as important, they can't be mass-produced due to reliance on sewing techniques that machines can't replicate and fabrics which are just as experimental and unlikely to ever be woven or knitted in real quantity.
* For that matter, a lot of fancy clothes in general. Try wearing a gown and stiletto heels to do...well, anything productive. To say nothing of corsets, hoop skirts and the like from the past.
** Open trench coats don't agree with car doors. Neither do capes and cloaks, [[CapeSnag which also tend to get snagged on just about anything]], as is demonstrated to lethal effect in ''WesternAnimation/TheIncredibles''. Loosely-fastened scarves are generally a bad idea in dense forests.
* Corsets, especially for tightlacing and body training. You can get an absolutely ''gorgeous'' waist and body with wearing a corset, but it can be extremely tedious and uncomfortable, and even painful. Good luck attempting anything physical activities wearing a corset.
* Traditional female clothing in Norway, [[http://www.nb.no/cgi-bin/galnor/gn_sok.sh?id=69110&skjema=2&fm=4 like what this Hallingdal woman is wearing]], dressed up for church. The head gear had to be put on with special care, and the whole set took an hour to finish. The last generation to use this regularly died out some time around 1980, and younger girls in this particular area switched to a more practical bonnet when dressing up. Nonetheless, this particular way of stashing was common in this area for ''300 years''.
* Cosplays with elaborate armor, props, wings, and the like are no doubt the result of hundreds of hours of dedication and hard work, and look excellent for photoshoots and for simply showing off. However, many of these cosplays can be uncomfortable to walk around a convention center in--just ask anyone who has tried to walk around in a 10-foot-tall cosplay of [[Franchise/NeonGenesisEvangelion EVA-01]] or the complete outfit and armaments of one of the ''VideoGame/KantaiCollection'' ship girls and they will tell you that strolling around the convention grounds without accidentally hitting people with their cosplay or wearing themselves out (depending on the weight of the materials and how warm the outfit is) is no easy task. Usually, people who output these kinds of grandiose cosplays will put them on for a photoshoot and then either remove the parts that inhibit mobility or change into something else to wear entirely when they want to walk around the event venue afterwards.
* Cashmere sweaters. Very warm, soft, and comfortable, but you can't put them in the washing machine; if you don't take them to a dry-cleaner they'll be ruined. They're also rather itchy.
* There are a lot of truly beautiful clothes out there for children and babies. A surprisingly large percentage of them are not machine-washable.
** Same goes for the dresses and gowns many starlets wear on the Red Carpet. They ''tend'' to be beautiful, but they cost an inordinate amount of money for something ''she's only going to wear once''. Notable pop star Music/LadyGaga seems to be [[StealthInsult parodying]] this, as some of her outfits are ''really'' out there [[MemeticMutation (the meatdress, anyone?)]] but, as her first performance on ''Series/SaturdayNightLive'' shows, she has some difficulty ''sitting'' in them to play the piano.
** To a larger extent the [[PimpedOutDress magnificent dresses]] used by both nobility and royalty in the past. Undoubtedly cool, but heavy, stiff, and being needed up to hours to ''be dressed'' in one -and that with the help of several servants or maidens.-
* The Roman Toga; the definite status symbol in Ancient Rome and made you look like a refined Patrician. But they were heavy, inconvenient, a hassle to walk around in, extremely uncomfortable in the hot Roman summer, and more or less completely disabled the use of the wearer's left arm. They had to impose a law forcing senators to wear them in meetings because they were so widely hated.
** It isn't really surprising: the toga was basically an oval or rectangular woolen sheet about a meter wide and 6 meters long, wrapped around the body several times. Imagine yourself wrapped heat to toes in a blanket — ''of course'' it was heavy and stifling: the classical toga was a thing that differentiated a ''quiritus'', or a free Roman citizen, who was expected to devote himself to politics, from a slave, whose purpose in life was to work, and who therefore wore a light tunic.
* Lots of clothing would come under this, such as extremely high heels that in many situations are crippling, but still popular for aesthetic reasons. Also exceptionally tight and restricting clothing, and clothes worn for [[FetishFuel fetish reasons]] that can be impossible to move in.
* A classic Japanese kimono is a clothing of an idle nobleman, plain and simple, and this is most evident in the formal women fashion with its straight and narrow silouette, which looks stunning, but forces its wearer into a painfully straight posture and barelly allows walking. Men's formal wear when in presense of a Shogun or Emperor also included an extremely long pleated trousers, called ''naga-bakama'', which were often 2-3 meters long and were ''specifically'' designed to restrict movement for increased safety of a visited dignitary, as they make a sudden attack impossible. Serving or working men and women wore shorter, knee-length or mid-thigh kimonos, often with narrow pantaloons called ''zubon'' for commoners, or wide, pleated ''hakama'' for upper classes and certain trades, and in hotter weather simply a ''fundoshi'' loincloth, all of which allowed for a much better freedom of movement.

[[folder:Gizmos & Gadgets]]
* 'Lightscribe' (and its rival [=LabelFlash=]) is a technology that allows you to 'print' high quality labels onto optical disks such as [=CDs=], [=DVDs=] and Blu-Rays. The process doesn't require paper, ink, or anything else beyond a special type of drive that costs only a couple of bucks more than a regular drive and special disks that cost only a tiny bit more than regular disks. After you've burned your data, you flip the disk over in your drive and 'burn' the label that you've designed in an easy-to-use labelling program; after a few minutes, a high-quality, high DPI label is embedded into the 'label side' of the disk surface. Unfortunately, it takes about 15 minutes to 'burn' a Lightscribe label, and it takes multiple repeated 'burns' to get an image of satisfactory contrast. You might have a Lightscribe capable drive and not ever know it, because simple permanent markers are just ''faster''.
** Similarly, they also make "printable" (matte white upper side) [=CDs=] and [=DVDs=] for use in certain printers. Just don't put them in a high-speed drive, as the rotation speed can sling the ink off of the disk, gumming up the drive.
*** That being said, [=LightScribe=] and [=LabelFlash=] are genuinely useful for people who have bad handwriting.
* Early portable MP3 players all had several features that put them firmly in this category.
** [=CD/MP3=] players were cheap and had significant storage capacity, but they were often difficult to use on the go (anti-skip technology mitigated, but never entirely eliminated, the problem) and preparing their media was a massive hassle. Want to change one track in your 700MB, 160-track CD? Gotta buy a new one. Ah, but you foresaw this and burned it on a rewritable! Nope, gotta buy a new one anyway, because the wear-and-tear of portable use scratched the CD-RW to hell and now your burner doesn't want to know about it. And burners of the time were painfully slow, too - writing 700MB at 4x speed was a half-hour affair.
** Hard-disk players had rapid interfaces, no skipping problems and you could effortlessly change their content as you saw fit - and for the time they held a ''massive'' amount of music. Unfortunately they were eye-wateringly expensive, often had questionable battery life and were frightfully delicate - if you dropped one even a short distance while the disk was spinning you were almost guaranteed to end up with a brick. Often the drive would die after some use even in players that weren't dropped, because no hard disk likes being jostled around in a pocket.
** Flash-based players could be used while taped to a jackhammer and they'd keep working, they could have their content modified at will, they were very lightweight and had great battery life - but flash memory technology was in its infancy at the time, and you could either have laughably small capacities (like, two hours of music, down to ''half an hour'' for the very first models) or ''absurd'' price tags. They eventually matured to their current state and eliminated all competition, but it took a good few years.
** Rob Malda of Slashdot was famously [[ItWillNeverCatchOn unimpressed]] with the [=iPod=] for the reasons mentioned above. "No wireless. Less space than a Nomad. Lame."
* dbx emerged as a competitor to Dolby noise reduction for consumer audio tapes, but was hampered by the fact that while Dolby recordings were perfectly listenable without decoding equipment, dbx recordings were unlistenable despite higher sound quality than Dolby with properly-equipped recorders.
* Listening to music at extremely high volumes. Yeah, it might give your music that extra oomph, but if you listen at maximum or near-maximum volume all the time it'll be only a matter of a few years or even months before you can't enjoy music at all anymore. Plus, depending on what kind of headphones you're using, the sound may leak and annoy people around you.

[[folder: High Technology]]
* Theoretically, anti-matter would be an incredible fuel, with every gram allowing for prodigious amounts of energy - making possible things such as far-space travel, or tiny powerplants that could energize entire countries. Only problem is, anti-matter is astronomically expensive (62 ''trillion'' dollars per gram) and slow to produce (to the point we've only ever managed to make a few hundred atoms), very complex to contain (a momentary containment failure of a significant quantity could result in explosions such as the human race has never yet seen) and has bad shelf life (varying from a few seconds to a few minutes).
* Any modern technology when it was in its early stages. The ENIAC, arguably the first digital computer, took up a room. The first cell phone weighed 80 pounds (36 kg). The first modern cars from around a century ago were not only unreliable, but there weren't that many decent roads to drive them on, or very many stations to refuel them at. And before that the first trains were just as bad (cinders from the steam engines starting fires, later on the wood burning stove in a wooden framed car being a fire hazard (and wooden framed cars are no protection in a crash), the rails (which were metal straps on top of wood) impaling people through the floor of the carriages, horribly slow by modern standards, etc...). This is why the ItWillNeverCatchOn page for [[ItWIllNeverCatchOn/RealLife real life]] is so long.
* The Manned Space Program. There is nothing for scientific pursuits that a manned mission can do that can't be accomplished by an ummanned vehicle for a fraction of the cost. [[RuleOfCool But it's too cool to resist.]]
* [[http://en.wikipedia.org/wiki/Project_Orion_%28nuclear_propulsion%29 Project Orion]]: Using nuclear explosions to propel a spacecraft. (Un)fortunately, the project was shelved after various test ban treaties. However, there were plans to build a freaking ''[[http://www.projectrho.com/public_html/rocket/realdesigns.php#id--Project_Orion--Orion_Battleship battleship]]'' with enough firepower to blast the Soviet Union into the Stone Age and have China for dessert. Thankfully it was shelved when the planners realised that it's essentially a game for two.
** Too be fair, the only things that made the spacecraft impractical were legal issues. From an engineering perspective, it was perfectly reasonable, even if it did sound a little over the top.
* The concept of a SpaceElevator sounds cool: Bringing materials and people up to orbital altitudes without needing fuel-burning rockets. However, many issues prevent the concept from working in practice, the threat of meteors and satellites colliding with the elevator cable being an obvious concern. As mentioned above though, most new technologies start out impractical and require ''a lot'' of work to bring into the realm of feasibility, space tethers are far from even the proto-type stage.
* Back during the Cold War and the Space Race the USA got the Saturn V rocket working, and the USSR wanted something better. Enter the N1, a massive five-stage rocket intended for launching space stations and other large cargo. It was properly huge and employed the novel concept of a cluster of smaller engines instead of the traditional four or five big ones. This gave it a significantly higher thrust than its American counterpart... in theory. In practice the higher thrust didn't actually give it a better lifting capacity, and the engine cluster required complicated plumbing that was never able to withstand the forces and vibration of launch without exploding the whole damn thing to bits. The second launch crashed back on the pad and caused one of the most powerful non-nuclear explosions ''ever'' recorded; though that probably qualifies as awesome in the traditional sense of the word, it wasn't exactly what the Soviet engineers had in mind.
** The choice of clustered (relatively) small engines was not due to such cluster being better, but due to the political infighting. Those who were able to produce big engines were intensely disliked by Korolev, and those he was on speaking terms with had no such experience...
** The first stage rocket engines used by the Saturn V had a different problem. They were actually a bit too powerful for 1960s technology to completely handle. (Let's put a human sized handle on this: Sure the engines each delivered around 1.5 million pounds of thrust, but who can grasp that? Instead, try this: Each had a rocket-fuel driven turbopump to pump fuel and oxidizer to the main engine. Those turbopumps produced roughly 55,000 horsepower. Each. Just to pump the gas.) NASA had a large enough budget to work around this problem and completely redesign the Apollo spacecraft after the Apollo 1 fire that killed 3 astronauts. The center engine of a Saturn V was programmed to automatically shut down before the end of the 1st stage burn when the acceleration rate passed a certain point or when pogo oscillations were detected. Both of those could destroy a Saturn V during launch. The Saturn V was designed so that it could lose a first stage engine part way through the climb to orbit (which did happen twice) and still make it to the moon and back.
* During the gas crisis of the late 2000s, there was interest in crop-based biofuels as an alternative energy source to oil. The appeal to environmentalists was obvious on the surface — biofuels are made from plant oils rather than petroleum, and as such, they're renewable, generate less pollution, and has a lower carbon footprint. Furthermore, as many biofuels can be extracted from homegrown agricultural crops, there was additional appeal for energy independence. However, while the actual biofuel product itself is inexpensive and environmentally friendly, the process of mass producing it isn't. These fuels require more land, leading to further deforestation that only released trapped carbon and thus increasing global warming. It didn't help that growing biofuels siphoned resources like water away from growing food crops, leading to food and water shortages. Subsequently, most businesses and governments have shelved the notion of immediate replacing petroleum with biofuels, though this idea of sustainable biofuels may become viable again provided that they can be successfully extracted from non-edible and sustainable sources like algae.

[[folder: Inefficiency]]
* [[http://www.youtube.com/watch?v=EKL6elkbFy0 Sharpening a pencil with a CNC Lathe.]] As a commenter pointed out, it's 90 euros for an hour with the machine, but 10 cents to buy a new pencil.
* Gambling for money can be perceived as this because it is possible to [[WealthyEverAfter win a lot of money]], but hardly practical considering all commercial gambling is [[SchmuckBait designed with something else in mind]].
** Card counters, rounders, folks who teach games, and professional poker players all beg to differ. Note that most such things are perfectly legal. MIT's famous team, inspiration for the fictional film ''Film/TwentyOne'' and a few more accurate books and documentaries, documented earnings near $170 USD per hour. Adjusted from 1982 dollars to 2012, that is nearly $380 USD per hour. Of course, a simple look at [[RealityEnsues the ratio of successful card counters, rounders etc. to folks driven to the poor house by their gambling]] should give any thinking individual pause. Also, some casinos have people in security who know how to spot card counters and rounders and will boot out anyone trying to do so.
*** Playing against the house is always this trope. Even the most successful playing teams required massive investments of capital (to weather long losing streaks) and incredible investments of time. The aforementioned $170/hr earnings is RAW revenue, which doesn't take into account the time for training or the ROI for capital. The actual numbers point to the investors making about a 50% profit over 2 years, and the actual players making something on the order of $10/hr accounting for all the time spent. In other words, the MIT players would have been better off working at Dunkin Donuts. Playing against others, on the other hand, can certainly be profitable (mostly because of the large number of mediocre players).
** Texas Hold 'Em for profit is also possible, as a low enough drop[[note]]The amount of money the house takes from each hand[[/note]] combined with low blinds can allow a patient player to have a slight edge provided they can properly calculate the odds of a win vs. the reward contained within the pot relative to their own bet, but it's a long game with a ''very'' slight edge of usually no more than a few percentage points, meaning that mathematically, you'll end up with more money than you started if you play long enough and don't make too many mistakes, but even that doesn't prevent you from having runs of poor luck where you end up in the hole temporarily.
* Dubai seems to be the epitome of the high tech, ultramodern city with its numerous flashy skyscrapers and ambitious building projects. However, the city itself lacks critical infrastructure that is taken for granted in literally any other industrial nation, such as a centralized sewer system. Though the city has adequate treatment facilities to process all of the waste it generates, the problem is actually transporting the waste to said facilities. With no pipes or sewers, the majority of the city's waste is carried by tanker truck, which can lead to long queues that can force a drive to wait at least 24 hours. It's not uncommon for tanker truck drivers to simply dump their waste wherever they can rather than wait.
* Many modern skyscrapers are a perfect example of this, particularly the kind that were built or started during the relatively recent property bubble of 2002-2008. Examples like the Burj Khalifa in Dubai (in the UAE) or the towers in Mecca were an example of what can happen when a few megalomaniac oil barons with access to Western resources (architects, engineers, and credit not locally available in the Middle East) build things for their own egos, but completely forget about cost and practicality. The result was more fuel a property bubble that helped puncture the world economy, depress growth rates in those countries, and may have indirectly sparked the Arab Spring. Mostly empty skyscrapers may look cool from a distance, but economically, they are a gargantuan waste of resources. It gets even worse when one considers the opportunity cost.
** Which is compounded by the fact that the Burj Khalifa is not not even connected to a sewer due to Dubai's lack of a centralized sewer system. All of the waste the building generates is stored in a massive septic tank which has to be regularly emptied by entire convoys of tanker trucks, which have to physically carry all the waste to the nearest treatment plant.
** When a "megaproject" looks like it has been grafted onto a much poorer or smaller community that looks like it cannot support such a project, it generally is an example of this trope, like a giant hotel in North Korea, or Romania's oversize Palace of the Parliament that destroyed an entire neighbourhood in its contruction.
** Speaking of which: the North Korean "Ryugyong" hotel, also known as the "Hotel [[DoomyDoomsOfDoom of Doom]]", is a massive, modern-looking palace that was to be the "tallest hotel in the world", had it actually been completed before someone else's hotel had snatched that title. It suffered numerous halts in construction, and was later deemed unfit for use and built so badly as to be structurally unsound - with things like concrete spontaneously breaking apart and ''crooked lift shafts''. North Korea ran out of money before completing it, with some sources reporting the hotel costing the country 2% of its entire GDP during the years it was being built. It sat unused and decaying for years, and even now that a telecom group has been fixing what parts of it can be fixed and seems to actually, really be on the verge of opening it, only small parts of it will ever be used, as the rest is beyond repair.
** It's been "completed", though it has yet to open. Parts of it are unusable.
** This is a situation that is OlderThanDirt. Most of the most fabulous of the Ancient Wonders were built to satisfy the egos of the local rulers or city authorities. They were unrivaled architectural achievements that attracted the envy of all while simultaneously being incredibly expensive and of very little practical use. Particularly in AncientEgypt, where it was not uncommon for a Pharaoh's monument building to leave the nation bankrupt. The Pyramids of Giza are a notable exception: far from being a drain on Egypt's wealth, the trade routes and associated infrastructure needed to raise the Pyramids became the very source of Egypt's immense wealth and economic power.
* Cooking with lava. Not lava rocks, ''[[Film/AustinPowersInternationalManOfMystery liquid hot magma]]''. A favorite demonstration of Syracuse University's Department of Earth Sciences' "[[http://lava-dev.syr.edu/ Lava Project]]" is to [[http://www.businessinsider.com/steak-cooked-lava-grill-meant-bbq-syracuse-university-2015-5 grill steaks with a stream of lava]]. Unless you like your steaks cooked ''very well done'', it's obviously not a practical way to cook anything.
** [[IncrediblyLamePun Of course we lava good barbecue]].
* Wireless Charging is, as of 2017, this. Sure, it is indeed a neat little toy - no cables to get in the way. So why is it less common and why didn't the ''UsefulNotes/NintendoSwitch'' use it, and use the outdated cords? Because those cords are not only faster, but more efficient. More energy is being given off as heat than is going to the device. Heat is also not good for batteries, either.

[[folder: Locomotive & Maritime]]
* [[http://inhabitat.com/china-developing-traffic-straddling-bus-that-drives-over-cars/ The Chinese Vehicle Straddling Bus,]] admit it; that thing looks all kinds of awesome. The idea, presumably, is to create a bus that is more convenient than its lane hogging brother. What they have actually done is invent a bus that if it accidentally swerves, to even the smallest degree, it will cause a three car pile-up - a prospect even more frightening when you add the prospect of many tons of bus landing on your head. Its doors are 9 feet above ground, entailing a complete refit of every bus stop on its route. Oh, and don't think this is just some crazy concept vehicle - the Chinese are fully planning to not only bring this thing into full service by 2011, but also sell it to America.
** It's actually a tram and it runs on rails. Still, this vehicle will be unable to get through busy traffic any faster than a regular motorcycle because there might be a [[EveryCarIsAPinto car]] on the rails. It may also have slight issues with bridges and overhead power lines. In the end, it is impractical in cities and unnecessary between cities. Maybe Chinese cities are different?
** They've finally tried to test it in 2016, repurposing a stretch of a road for that without bothering with permissions. When the authorities wanted to have a chat about that, it turned out that the trials have failed and the owners decided to disappear, leaving the "bus" at the improvised test track. Where it demonstrated all it's failings by blocking the road and creating traffic jams.
* Speaking of Russia, consider the Soviet 12,000hp diesel locomotives. Yep, twelve thousand horsepower in what counted as one, single locomotive. It took a while for the Soviets to realise they didn't need that much power. The Baikal-Amur Mainline for which the first four-section, 12,000hp locomotives were built was single-track with sidings too short for anything that justified more than 9,000hp. And before goods trains could grow heavy enough for that much power elsewhere, [[TheGreatPoliticsMessUp the Soviet Union was dissolved]], and the post-Soviet economy didn't generate enough cargo to make trains that heavy.
** One year after the first 4TE10S was made, the Soviets managed to put 6,000hp into one single, one-section, one-engine diesel locomotive, the [[http://translate.googleusercontent.com/translate_c?hl=en&ie=UTF-8&sl=ru&tl=en&u=http://scado.narod.ru/catalog2/r_t_tae136.htm&rurl=translate.google.com&usg=ALkJrhjyoxbYvmtxXf_1QFWWIKms1hVfHg TE136]]—''long'' before EMD produced their own 6,000hp engine, the [=SD90MAC=]
** The Soviet [[http://www.aqpl43.dsl.pipex.com/MUSEUM/LOCOLOCO/russ/russrefr.htm AA20]] was awesome and impractical for one and the same reason: it was a 14-coupled steam locomotive. It also ruined tracks and destroyed every switch it went through.
** The Swedes seem to have built a somewhat more practical awesome locomotive for hauling ore from Kiruna to Narvik. The [=Dm3=], a 1D+D+D1 articulated electrical locomotive delivers 7600kW (just a tick over 10000hp) and hauls 5200 tons.
** Romanian [[http://cfr.stfp.net/Pic/47/%5E4707731591_53_0477773-2:1.jpg Class 47 locomotives]] are single-unit electric locomotives with continuous 6600kW (almost 9000hp) of power, designed to take on trains loaded with 3000-3600 tonnes on mountain lines. However, most of them are used for passenger trains, which is a waste of potential.
* [[UsefulNotes/DeutscheBahn Deutsche Bundesbahn]] built their [[http://upload.wikimedia.org/wikipedia/commons/7/71/103_235_Dresden_Hbf.jpg Class 103]] single-unit electric locomotives with continuous 7400kW (one-hour peak power output of 7700kW / 10,400 hp). Despite being designed to haul 5-to-7-car passenger trains at 200 km/h (125 mph) with high acceleration, they pulled heavy intercity trains with sometimes 12 or 13 cars at the same speed from 1979 on. Yes, they could do that with ease. No, they couldn't withstand that workload without wearing out alarmingly quickly.
** To make things even worse, they had a tendency to wear out even quicker when constantly run below 160 km/h (100 mph)[[note]]The speed of 160 km/h is significant in Germany as it is the maximum speed legacy signaling allows. In other words running trains above that speed requires improvements in infrastructure which at the time were not at all common - even in 2016 the Intercity Express (in many ways the SpiritualSuccessor of the Class 103) has significant stretches of legacy tracks allowing speeds no higher than 160 km/h[[/note]], so using them in less straining long-distance services was pretty much out of question, too.
* American railroads had such stuff, too. Check out the [[https://en.wikipedia.org/wiki/PRR_FF1 Pennsylvania Railroad FF1]]. At the time, 4,000hp was a lot, the technology was practically space-age. But, the locomotive was simply too powerful for period rolling-stock, and would regularly pull out couplers or shove cars off the rails.
** The [[https://en.wikipedia.org/wiki/Budd_Metroliner Budd Metroliner]]. An EMU designed by and for the Pennsylvania Railroad to run top-notch high-speed services in the Northeast Corridor. Its maximum speed was beyond 160mph. Not that the Pennsy had any stretch of track that would have allowed for anything close to that speed.
** This seems to be a consistent problem for the Pennsylvania Railroad because they built the [[http://en.wikipedia.org/wiki/PRR_T1 4-4-4-4 T1.]] The T1 was powerful, fast, and looked cool. It was also a maintenance nightmare, ate coal like nobody's business, and was prone to wheelslip, which will destroy an engine's running gear in a matter of seconds if not quickly corrected. All 52 were scrapped within ten years of production.
** Their predecessor, the sole [[https://en.wikipedia.org/wiki/PRR_S1 6-4-4-6 S1]] No. 6100, was even more awesome and more impractical. It was the most powerful express steam locomotive ever built, but it carried only 40% of its weight on two mechanically independent sets of four driving wheels each. These were overwhelmed by the sheer power of the boiler which made wheelslip almost inevitable at any speed below 50mph. Its main advantage was that it could reach speeds way beyond 120mph. This, however, wasn't very useful as there was very little track on the Pennsylvania system that was straight and flat enough for it to operate at high speed excepting a few places in the midwest.
** [[http://www.aqpl43.dsl.pipex.com/MUSEUM/LOCOLOCO/triplex/triplex.htm Triplexes]]. So how can the tractive effort of a locomotive be increased? More drivers under the tender. The problem was, the boilers simply didn't generate enough steam to feed that many drivers. It was practically useless past walking speed.
** Streamlined express engines, especially the 1930s-type steam engines, are fast and pretty, but they are expensive to manufacture, often require specialized crews, and cannot be used on any train except the express.
** German streamlined steam locomotives not only looked cool but actually saved some fuel. The main reason was because the streamlining was a shroud wrapped around ''the entire locomotive'' from the top of the boiler almost down to the rails. However, the fully-enclosed running gear lacked ventilation and was prone to overheating, and maintaining it through the small hatches on the sides was difficult.
** The [[http://en.wikipedia.org/wiki/2-6-6-6 2-6-6-6]] [[http://www.steamlocomotive.com/allegheny/ Allegheny-class]] steam engines of the Chesapeake and Ohio could produce 7000 horsepower on average, but they weighed more than the Big Boy, and the 40-ton axle weight left the monsters restricted to only the heaviest lines.
** Speaking of Chesapeake & Ohio, their [[http://www.aqpl43.dsl.pipex.com/MUSEUM/LOCOLOCO/chesturb/chesturb.htm steam turbine-electrics]] existed for less than three years between construction and scrapping. The modular construction promised to make repairs easier than on conventional steamers. Unfortunately, they were so complicated that it took a lot longer to find any faults in the first place.
** The [[https://en.wikipedia.org/wiki/Baldwin_60000 Baldwin 60000]], one of the largest locomotives ever made. The designers intended it to be the train of the future, but its sheer size meant that the controls were too complex for most engineers to operate, and the firebox tubes had a nasty habit of bursting. If that weren't bad enough, it was so heavy that the test run damaged the rails it was on, thereby ensuring that the railroad companies would not be interested. It didn't even go faster than any other locomotives. Only one was ever built, and it's been stationary in a museum for the last eighty years.
** The [[http://www.railpictures.net/photo/486227 Union Pacific Coal Turbine]]. ExactlyWhatItSaysOnTheTin: So you have plenty of coal at hand, enough to feed steam monsters like the Challenger or the Big Boy. But you want to go away from steam with its abysmal efficiency. What do you do with all that cheap coal? Burn it in a turbine like you would burn liquid fuel in a gas turbine. But wait, you can't simply dump pieces of coal into a turboshaft engine, they'd take too long to burn, so what do you do? Grind the coal to dust in the tender that's been converted to a mobile coal bunker. Why that's a bad idea? Because the coal dust will be accelerated to very high speeds in the turbine whose blades will be under constant bombardment of tiny pieces of solid fuel — which actually don't come out of the grinder in the tender ''that'' tiny. Also, the sulphur in the coal will turn into sulphuric acid which will eat away your precious turbine blades. Maintenance of this monster (which still doesn't have enough space for a cab so it has to be [=MUed=] from an Alco PA-1 running ahead which eliminates the need of firing up the turbine for marshalling) will be so costly that you could also have burned mineral oil in the first place.
** [[https://en.wikipedia.org/wiki/Union_Pacific_GTELs Which the UP did as well]]. Their first gas turbine engines ran on 16 wheels and had 4,500hp. The prototype had an on-board fuel reservoir and two cabs, but gas turbines are horrendously thirsty, turbines of that size even moreso, and the range of that locomotive was so minimal that the production units were built with only one cab because the other end was coupled to a 12-wheel oil tender. The third generation became a massive three-section type with 8,500hp which could be increased to 10,000hp by mounting additional electric motors on the tender axles. All these locomotives ran on Bunker C oil which was pretty much refinery leftover and therefore dirt cheap, but they used such insane amounts that the UP had to keep them on the lines as much as possible because leaving them standing with their turbines running was still too costly, and the already bad wear on the turbines would only increase with constant shut downs/start ups. Besides, Bunker C didn't stay that cheap when new uses were found for it in the plastics industry. Now imagine what would have been, had these locomotives still been around by the time of the 1973 Oil Crisis.
* Even England, the motherland of railways, isn't safe from this.
** In the late 1940s, [[http://www.bulleidlocos.org.uk/_ldr/ldrClass.aspx Oliver W. Bulleid decided to pretty much reinvent the steam locomotive with Southern Railway's Leader class]]. It was a steam locomotive that didn't look like one at all but rather like an early diesel. Instead of having a set of drivers in a rigid frame coupled by rods and directly powered by steam pistons, it had steam motors in its two six-wheel bogies, and its track view surpassed that of all other British steamers because it had one driver's cab at each end. It actually worked pretty well.\\
Otherwise, it was quite half-baked. It had one lateral aisle through the entire engine room. This, however, required the boiler to be placed out of centre, causing the locomotive to be unbalanced. The countermeasure was to fill scrap metal under the floor boards in the aisle which in turn made the locomotive too heavy. The fireman's room was in the middle of the locomotive and prevented any communication between him and the driver; it was also badly ventilated, and the fireman would have burned his shins on the hot air from the firehole, hadn't he worn protectors; and in the event of the locomotive falling over, he wouldn't have had a chance to get out unlike on conventional steamers whose cabs have an open rear end.\\
The best part: The first Leader, 36001, wasn't a [[FlawedPrototype one-off prototype]] but the first of the actual serial production run. When the Leader project was stopped, 36002 was almost finished, and work on 36003 had commenced.
* Supertankers. They have reached their maximal practical size already in the late 1970s, and [[AwesomeMcCoolname Seawise Giant]], launched 1979, demonstrated [[http://en.wikipedia.org/wiki/Seawise_Giant with all her 450 m length and 657,000 tonnes displacement]] that building any larger is impractical. ''All'' the supertankers of her size [[http://en.wikipedia.org/wiki/List_of_world%27s_longest_ships have been scrapped]], and the [[http://en.wikipedia.org/wiki/TI-class_supertanker largest supertanker currently in service]] carries roughly ''half'' the tonnage of oil Seawise Giant did.
* Isambard Kingdom Brunel's final project, the SS ''[[http://en.wikipedia.org/wiki/Ss_great_eastern Great Eastern]]''. Being five times larger than the biggest ship that came before it, and remaining the biggest ship in history for 40 years, it was certainly pretty awesome. But 'practical' is not the word to use when such an insanely expensive ship, which has capacity for 4000 passengers, carries just over ''forty'' on its maiden voyage.
* For that matter, Brunel's broad gauge. While the standard gauge rail lines had a loading gauge that was much too small, causing problems to this day with bilevel railcars and when trains cross from continental Europe (the first generation of Eurostar had to be custom built for a lot of British quirks, including the rather narrow loading gauge), Brunel's broad gauge caused problems in the opposite direction. You see, the main reason for a small loading gauge is that it saves a lot of money. Brunel's trains could only run on broad gauge lines and he could not share his tracks with other railroads nor have his trains run along other railroad lines. In addition to that building to his exceeding standards was fine on main lines but prohibitively expensive on branch lines and just like airlines today operate feeder services at a loss to get passengers for their main lines, railways without a feeder service would have much lower passenger numbers. The last broad gauge lines were converted to standard gauge before the 19th century was over. Unfortunately, Spain made a similar mistake in choosing a non-standard broad gauge, because [[WhatAnIdiot they thought it would bring advantages]]. It didn't.
* There is no technological barrier to making [[UsefulNotes/HighSpeedRail high speed trains]] go 400 km/h or even faster than that. In fact, some trains in revenue service today have reached that speed in unmodified test runs. However, due to many factors, including aerodynamics, running trains at those speeds draws way more energy than the increase in speed it produces. Add to that the fact that most trains have to - you know - stop once in a while to load and unload passengers and the difference between a 300 km/h and a 400 km/h train becomes a few minutes of time saved for a few ten thousand euros of money wasted on electricity to accelerate to those speeds. Current Maglev technology is more energy efficient at those high and very high speeds, but it has its own downsides and also fits this trope in many ways. Another problem with extremely high speeds is that tolerances become much smaller and braking distances become longer (reducing capacity of any given line), not to mention the infrastructure that does not always support those speeds. In the high speed networks of many countries BoringButPractical solutions like upgrading a curvy legacy line from 80 km/h to a straighter alignment allowing 200 km/h is much more cost efficient and saves much more time along the whole run than high top speeds.
* [[https://en.wikipedia.org/wiki/Turbojet_train Jet engine powered trains]]. Nuff said.
* Similar to Brunel's broad gauge, San Francisco's [[UsefulNotes/BayAreaRapidTransit BART]] has also suffered from building its own wide gauge. While the gauge provides a smooth ride and a degree of safety in the earthquake-prone Bay Area, the gauge has made repair and replacement of the aging system's equipment extremely difficult, as they can't use any track replacement equipment designed for other railroads. Mechanics have resorted to buying parts off of {{Website/EBay}} because of the nonstandard gauge.
* There's a reason there aren't a whole lot of monorail-based transit projects. The key problem is that the whole monorail system has to be grade-separated. That is, it has to be completely off the ground. The costs involved in building monorails means that it's most cost-efficient to build a single track. Switching tracks has been prohibitively expensive and almost impossible until very recently. Most monorails are limited to short loops around theme parks and airports. Monorails are held up along with [[IWantMyJetpack jetpacks]] as prime examples of {{Zeerust}} rather than practical forms of transportation.
* [[https://www.google.fi/search?q=world%27s+tallest+bike World's tallest bike]]. Unsurprisingly.

[[folder: Pets]]
* Exotic pets, or just numbers of ordinary ones, were used to show off the owner's wealth and easy life. The most common ones were [[PantheraAwesome big cats]], [[EverythingsBetterWithMonkeys monkeys]], {{bears|AreBadNews}}, [[GoingToSeeTheElephant elephants]], and non-native birds, but anything that took their fancy was fair game. Royalty and nobility were also known for ''herds'' of horses, when even one horse was a sign that the owner was well above everyone else.
** Domesticated servals. They embody the best character features of the cat and the dog, they're fast and agile and in general great fun to have around. They're also extremely expensive to buy, require rather more food and open spaces than your average cat, and need very caring and committed owners.
** This is the origin of the term "white elephant". The legend goes that the kings of [[UsefulNotes/{{Thailand}} Siam]] would gift white elephants to people they found troublesome or obnoxious, so as to ruin them financially with the costs of their upkeep. Since white elephants are held to be sacred in both UsefulNotes/{{Hinduism}} and UsefulNotes/{{Buddhism}}, there were laws protecting them from being killed or used for labor, meaning that the recipient of this gift now had to care for a large, hungry beast that he couldn't get rid of or put to good use.
** For Asian households, Arowanas are considered to be a good omen on your house (the legend goes that they're juvenile forms of Chinese Dragons). However, a single silver Arowana can cost an upwards of 1000 USD young, and several thousand when matured (rarer colored ones go for double or even triple the price of the silver ones). And they're not easy to keep either; they are carnivores and must be fed a specific diet (usually live), and when matured can grow to a length of two feet and become strong enough to ''break the tank they're in''. Wealthy Asian businessmen are known to not only buy the most high-end tanks for them, but also specifically hire people to keep these things alive (which is pretty much a round the clock job). It becomes somewhat HilariousInHindsight that the original legend said that the dragon born of an Arowana would come back to either punish a bad owner, or shower the owner with riches (anyone actually rich enough to take care of one would probably be better off just spending the money!).
** Even the basic octopus is very expensive and has specific needs that requires extensive planning to keep as a pet, made worse by the surprising frequency people try to buy them for their home aquariums. First, their extreme sensitivity to changes in their water combined with their messy eating habits means that their water needs to be changed ''very'' frequently. But most prominently, the fact that they are so intelligent means that they are prone to boredom and escape attempts, meaning they need tanks with locks and toys just to keep them entertained. And what does even the most dedicated octopus owner get under the best conditions once all of these needs are checked? A pet that requires a lot of work to keep healthy and entertained and whose natural lifespan almost guarantees they won't live more than a year or two anyway.
* Dog breeds that are extreme distortions of the original model, such as bulldogs with such big heads and narrow pelvises that they can't give birth naturally; their puppies always have to be delivered by Caesarean.
** Or pugs, which will self-destruct (that is, grow infections and illness, quite possibly leading to death) if not cared for very scrupulously.
** Cat breeders are doing the same genetic damage to several breeds. Purebred Persians have breathing problems, eye problems, and are more likely to have stillbirths. The original breed type is still around (usually called Traditional Persian or Doll-Face Persian), but cat shows won't let them compete because they don't have the malformed skull that has become breed-standard.
** On the other side of things, a few bulldog breeders have realized that the current breed-standard for bulldogs is unhealthy to the well-being of the bulldog so they're setting a new standard to make it more robust (and even looking like how the breed was in the 1800s).
* Cloning your pet. Imagine bringing your beloved and amazing dog or cat back from the dead! Only cloning doesn't work like that in real life. The clone may be genetically identical, but it'll pretty much be a unique and new individual. Not to mention that cloning would cost a ton of money to essentially get a pet you could easily find at a local pet shelter for much less.

[[folder: Sports & Martial Arts]]
* In the [[{{tennis}} tennis world]] in 2007, an exhibition match between Roger Federer and Rafael Nadal called Battle Of The Surfaces was held. Federer vs. Nadal on a [[http://my.opera.com/ARA77/albums/slideshow/?album=256440&picture=3788323 half-grass, half-clay court]]. So awesome. So impractical.
** In 2011, Federer vs. Nadal on a tennis court [[http://www.dailymail.co.uk/sport/tennis/article-1343739/Rafael-Nadal-Roger-Federer-really-walking-water-Qatar.html floating on the ocean]]. Jesus, that's cool.
* Most martial art styles you see in the movies is this trope. You see all those cool backflips, dodging moves that Creator/JackieChan and Creator/BruceLee know? They're real, though choreographed for movies. The most effective techniques are the simple ones you learn early. Some less-than-practical examples from Shaolin Kenpo:
** Defensive Maneuver Eleven. During the course of that, you redirect a punch, knock them down, break your attacker's legs ''three times'', knee them in the spine, and leave them face-down on the floor after kidney-shotting them. Good luck doing ''that'' one in real life.
** Another offensive technique merely involves grabbing the top of a person's arm while they punch, slapping their ears, and then kneeing them in the face. You'll notice the technique begins with what is effectively ''catching a punch''.
** Creator/BruceLee once commented that a person who has trained for a year in boxing and a year in wrestling could beat any eastern martial artist in a no-holds-barred fight.
* It's difficult to say whether or not basketball (mostly the NBA) subverts or plays this trope straight with slam dunks. Many NBA players will not hesitate to perform a flashy dunk if they have the chance, mostly on fast breaks. The 360s, reverse dunks, and windmills look a hell of a lot cooler than standard dunks, but they're still worth the same amount of points... and the fancy dunks have a higher chance of missing. However, some people are of the belief that performing flashy dunks can spark a home crowd (or deflate an opposing crowd), thus giving the team more momentum than a normal dunk would.
** The defensive equivalent of a flashy dunk in this regard is blocking the shot so hard that you hit it out of bounds. Sure, you look like a badass in the process of stopping the team from scoring, but in most cases, having touched the ball last, you let the other side retain possession of the ball. A more practical technique would be to try to tip the ball softly toward a teammate and gain possession (that's not gonna make SportsCenter, though). Bill Russell, one of the greatest defenders and shot-blockers (if not THE greatest) in NBA history, has gone on record many times as saying that blocking shots out of bounds, unless absolutely necessary, is a basketball sin.
** This trope also applies with passing in basketball. Some players are simply incapable of making a routine chest pass (Jason Williams, formerly of the Sacramento Kings, was benched during fourth quarters because of this - after retiring from the NBA, he now plays a lot of exhibition matches, which give him a lot more room to try fancy passes) at all, and would rather risk a turnover by doing a flashy behind-the-back pass.
* Most ProfessionalWrestling moves qualify. Sure, they look cool and can be deadly if done incorrectly, but they would be completely useless in a real fight. Most of the throws usually require the opponent to assist, or at least allow it to happen, meaning they can be easily countered by a resisting opponent.
* The "ripped look" [[UsefulNotes/{{Bodybuilding}} bodybuilders]] have while on-stage during competitions looks awesome, but the bodybuilder is actually very low on body fat and might even be dehydrated. By comparison, if you look at world-class competitors for weightlifting and other competitions of strength, notice how few care about their overall body image (and some are even fat, making it StoutStrength) despite being the strongest men alive. Looking like you could bench 150 kilograms is not the same as actually being able to.
* Free-running, which is a descendant of the much more BoringButPractical [[LeParkour Parkour]]. Sure, it's cool to make all those backflips and land on your feet just to keep running, but the training, agility and stamina required are prohibitive for most people.
* In the UsefulNotes/NationalFootballLeague, many teams are tempted to draft a Quarterback first overall, given half a chance. However, there are only two ways to acquire the first overall draft pick: Either being the worst team in the league in the previous season or trading for it, which in effect means giving up either top tier players or several draft picks, which translates to less room for growing the roster and filling weak spots with better young talent. Sure signing the exciting new gunslinger who just won the Heismann Trophy and led his team to the national championship is ''tempting'', but even if he does not prove to be a bust (surprisingly common) he will most likely be surrounded by a team that ''earned'' their spot as the worst team in the league, and a relatively inexperienced new quarterback can sometimes be a ''detriment''. If the first draft pick was acquired in a trade, you might get a good team in the first year (when the new QB is still learning the ropes), but having given up all those picks to trade up to number one ''will'' hurt you in the years afterwards. BoringButPractical solutions like trading away first overall and / or building defense and the offensive line instead can be much more rewarding in the medium or even long term. However, this is kind of a LuckBasedMission, because in some cases the first overall pick really does live up to the hype, like both Manning brothers who have both won two [[UsefulNotes/SuperBowl Vince Lombardi Trophies]] a piece and Eli Manning is still active.
* In soccer flashy offenses like the Dutch Totaalvoetbal of the 1970s have many admirers and are admittedly a delight to watch, but they have netted the Dutch team a grand total of zero World Cup wins. Meanwhile Italy, which is well known for the more defensively oriented Catenaccio, which has been described as "stirring concrete" has won the World Cup four times. Sadly the flashy awesome offensive powerhouse of world soccer has nothing against the incredibly boring (but practical) style of just keeping the opponent from scoring until they make a mistake or are too exhausted. With very few exceptions, the best defense will win against the best offense when measured in goals scored/permitted per game. This is part of the reason why the amount of goals scored per game at the highest level has trended down ever since the 1954 World Cup set a record at 5.38 goals per game. Today it is below three and trending downwards still.
* Butterfly stroke on swimming. It is considered as the most difficult to learn and the most energy consuming swimming style, whilst it isn't the fastest (freestyle is). It has little use aside swimming competitions - breaststroke is the most energy-efficient overall swimming style.
* Martial arts aimed against a single set of opponents, such as jodo. Jodo was originally developed by Gonnosuke Musō [[CoolVersusAwesome after his defeat to Miyamoto Musashi]] and it is aimed against katana-armed unarmoured opponent to defeat him. It is next to useless against anyone who a) has any body armour or b) is armed with a different weapon.
* The UsefulNotes/NationalFootballLeague tries its damnedest to avert this trope. Over time the NFL has turned into ''more'' of a passing league and (arguably) BoringButPractical "three yards and a cloud of dust" offenses are becoming rarer and rarer in favor of high risk high reward gunslinger offenses and trick plays are usually encouraged rather than looked down upon. There was one area in which the NFL did play this trope straight for a long time, namely extra points. Teams that just scored a touchdown would get the ball at the two and a half yard line and get one extra point for a field goal from that position and two extra points for a touchdown. Statistics show that a field goal from so short a distance has a success rate well north of 99% and there is only a roughly 45% chance of the two point conversion being made, making the two pointer AwesomeButImpractical in all situations but games where one point is useless but two points make it a tie game. The NFL, however decided to move the extra point back to the 15 yard line (while leaving two point attempts at the same point), which has proven to make teams a little more inclined to go for two.
* Submarine (better known as underhand) windups in baseball. A truly skilled submarine pitcher can generate groundball outs and prevent batters from hitting fly balls at a 70% ground ball/fly ball ratio or better (the league average in the MLB is around 48%), and the unusual arm slot and motion enables them to throw pitches that no one else can, like literal rising fastballs (otherwise impossible due to air resistance), or changeups that seem to break upwards before they fade. The catch? It's ridiculously difficult to master. As of the 2016 season, there were no true submarine pitchers in the MLB, with only Brad Ziegler, Joe Smith, and Darren O'Day fitting the criteria of partial submarine pitchers (guys who throw from an extremely low sidearm slot, but not a purely vertical one). They are somewhat more common in the NPB and KBO Leagues of Japan and Korea, respectively, however.

[[folder: Weaponry]]
* Throwing knives fall into this category. They're fun as a hobbyist's toy, but the precision required to attack and injure a moving target is impossible to reliably use--especially since they're too light to have real stopping power unless you get that perfect shot, and any flinching of the target's might throw that off.
** Plus, you're basically throwing away your weapon, and giving it to your opponent.
** Applies also to throwing stars (shurikken), although they don't take years to learn (TheBladeAlwaysLandsPointyEndIn is TruthInTelevision for a weapon that has blades all around).
* Nunchucks. They're certainly a flashy weapon to show off with in martial arts demonstrations, and being able to master one's use requires a very high level of discipline and finesse. Unfortunately, they're very difficult to train with, and simpler weapons do their job better[[note]]Historically, nunchaku were adapted from grain flails, and they were used the same way a Western flail is: [[BoringButPractical by simply swinging it upside an opponent's head]][[/note]].
* Among civilian firearm enthusiasts, this trope is often known as "tacticool", describing a gun that's been dressed up with scopes, laser sights, flashlights, bayonets, bipods, and other "tactical" attachments that don't actually improve the function of the gun, and may in fact detract from it. Related is the stereotype of the "mall ninja", an inexperienced/ignorant gun enthusiast (typically a young man who's played too much ''VideoGame/CallOfDuty'') who obsesses over these sorts of guns. There are, of course, gun owners who embrace this to the point of deliberate parody, going out of their way to make the most ridiculous guns they can imagine, up to and including tactical ''[[SchizoTech muskets]]''.
* Fully-automatic machine pistols, such as the Glock 18, MAC-11 and Tec-9, when it comes to anything other than suppressive fire. They burn through ammo, rapidly overheat, jam easily and are very inaccurate. Although there have been some exceptions, like the Škorpion, Mauser M712, Micro-Uzi and Steyr TMP, most machine pistols can be easily replaced by more reliable, controllable and accurate submachine guns.
** In particular, the Ingram MAC-10 and MAC-11 machine pistols were good examples of this trope. Being more compact than submachine guns and being robust and extremely easy to manufacture, they possessed an ''awesome'' firing rate - almost double that of similar-looking Israeli Uzi machine pistol. Howewer, the extremely rapid firing rate and flimsy backstock also meant they were ''horribly'' inaccurate at any ranges beyond 20 m or so, earning a reputation of "bullet sprayers". It was also all too easy to shoot the whole magazine empty with just one squeeze of trigger. While some special forces got interested in the MAC-10, MAC did not get contracts and went bust in 1975. As well as that, the .45 ACP/9x19mm MAC-10 had its strengths, but the MAC-11 was a complete disaster. It was tinier than the MAC-10, but chambered in .380 ACP, which gave it extremely heavy recoil. The MAC-11 also had a faster rate of fire, which emptied the magazine even quicker than before and with the heavy recoil, made it practically inaccurate unless at close range.
* It's generally agreed among gun enthusiasts that, for self-defense and law enforcement purposes, anything more powerful than a .357 Magnum is essentially [[ThereIsNoKillLikeOverkill overkill]] if you're not built like an ActionHero... unless you expect [[BearsAreBadNews to be attacked by bears]]. If that's the case, then [[HandCannon .44 Magnum]] is the ''minimum'' recommended cartridge, or even better, to forget the handgun and pack a rifle instead.
* DualWielding:
** The GunsAkimbo style. Sure, [[RuleOfCool you look badass pulling it off]], but having a gun in either hand makes aiming and reloading impossible. Carrying two pistols in a hypothetical action movie scene, it is better fire them one at a time, switching to the second pistol when the first one is empty to delay the need to reload one.
** It's possible in real life, if you're a trained expert with years of experience. It's easier to learn to shoot one gun well than two guns with varying success.
** Dual-wielding swords may look awesome, but they're hard to use and aren't as useful as a single sword with a shield. No military culture ever used two swords in serious combat.
*** Though some historical armies (such as the medieval Portuguese) used a sword an a knife, it's still not much better. When it did pay off, [[RefugeInAudacity it was often because of its novelty]].
*** However [[UsefulNotes/{{Miyamoto Musashi}} Miyamoto Musashi]] taught the "Niten Ichi" two-sword technique, using a Katana and a Wakizashi (short sword) and used it quite effectively. He also recommended training with two long swords, one in each hand, in order to learn to not use two hands with your long sword. Once you learn that, you switch to the long sword and companion sword. Musashi actually discouraged the use of just one sword. (But then, Musashi was just THAT good.)
** SwordAndGun. While flashy, the sword isn't going to do you much good in real life over just using the gun, and you're limited to firing the gun with just one hand which makes aiming difficult, and can't easily be reloaded.
* IaijutsuPractitioner... if only you can actually USE it in the battlefield. Trying to kill a man with one stroke needs VERY close proximity.
* The [[RareGuns Mateba Model 6 Unica]], known to most people as the "Autorevolver". It's a revolver that cycles like a semi-auto, removing the need for a heavy trigger pull. It looks super cool, but it combines the drawbacks of both semiautos (less durable and more prone to malfunction) and revolvers (smaller magazine capacity and difficult to reload) into one rare and extremely expensive package.
** Cocking the gun semiauto-style is possible (for show, as otherwise you'd prepare the first shot by simply arming the hammer), but as the carriage lacks grippy surfaces you can only do it by... pushing on the barrel.
** The Model 6 Unica was also available as the Grifone, with a lengthened barrel, hand rest and stock, effectively turning it into a carbine. The Grifone was available in .454 Casull too, which is a ridiculously powerful round that's overkill in pretty much any conceivably practical scenario. And in those scenarios where it's not overkill (ie big game hunting), there are still plenty of better and/or less expensive options.
* Nearly all "collectible" "fantasy" type knives and swords are this. Lots of wicked-looking pointy bits, but you're at least as likely to injure yourself if you try to use them in combat, either from the excess pointy bits on the weapons or from the brittleness of the cheap steel used to make them. That's to say nothing of the fact that a barbed blade could easily get snagged in your opponent's body or armor, which could be very bad if the thrust didn't kill them, or they have friends.
* Any form of [[HumongousMecha giant robot]] in general. The very fact that these mechs have legs makes them easy to disable: just break the legs and they're useless. If there are going to be any giant robot warmachines in the real world, they will have less vulnerable means of standing upright, like tank treads - as in the case of Guntank. For now.
* The Desert Eagle handgun, especially in .50AE chambering. Awesome looks, awesome power, awesome boom, loved and used by every action hero ever, kills bad guys like nothing else. The concept doesn't translate well in reality though: excessively heavy and bulky, unmanageable recoil (to the point where fractured wrists are a very real possibility), expensive ammunition [[note]].50 Action Express rounds go for over 1 USD ''each'' in 2014. If that doesn't sound like much, you've never been to a range during practice shooting[[/note]], small magazine size and ''too much power'' ensure its status as a toy for rich people, but not a practical weapon. Deagles chambered in smaller calibers like .357 are marginally more practical, offering less recoil and a slightly bigger magazine capacity, but are still oversized, more finicky, and heavier than almost any revolver with the same chambering.
** It also sports two design choices that make it impractical for anything other than range use and occasionally hunting regardless of which caliber it's chambered in - it operates off of what is basically a rifle-style gas relay system (meaning that unjacketed rounds, such as those commonly used in .357 and .44 magnum revolvers, will quickly clog the gas valve, so the cheapest options for its already expensive ammo are a no-go) and uses a "free-float" magazine that will jam if there is any upward pressure placed on the magazine during cycling.
** Just about any handgun with more power than a .357 magnum is this trope in spades. The only logical purpose they could have is to kill big game, like moose, {{bears|AreBadNews}} or any of the Big 5. However, these handguns are still outclassed in every regard by the high-caliber rifles that hunters have been using for decades, so their only value might be as an emergency backup weapon.
** All types of handguns, even Olympic target pistols, are woefully inaccurate at long range. A rifleman can be trained in a few weeks (and hundreds of rounds fired) to hit an apple beyond 100 yards. To get the same performance from a handgun at 25 yards it takes years of training. So the gigantic .50 caliber round of the Desert Eagle may be awesome at a few yards if the bear charges you, but nothing else.
** Nearly all decently-powered pistol rounds actually have a much, much longer effective range than one might expect -- up to several hundred yards in some particularly stellar examples. Submachine guns like the 9mm caliber [=MP5=] and the .45 ACP caliber Thompson are effective out to about 150-200 yards, while there also exist rifles and carbines chambered to fire pistol rounds that have similar ranges and are often used for home defense. The problem is that, while rifles have stocks which significantly dampen the natural motion of a shooter's arms, handguns are subject to every tiny tremble and muscle motion of the wrist, resulting in the angle of the barrel changing much more unpredictably.
* Pistol swords. Sure, the idea of a sword and gun together sounds more efficient than just going SwordAndGun, as [[BayonetYa bayonet-fitted rifles]] have shown, but in practice, all one got was an overly heavy, poorly-balanced sword and a pistol that was difficult to aim properly.
* Large-capacity cylindrical magazines, such as the notorious 50-round drum on the Thompson SMG or the helical magizine on the futuristic-looking Calico M690. They allow a user to fire more shots between reloading, and look cool besides, but they're notoriously unwieldy, prone to malfunction, and take an age and a half to restock. Military forces by and large have decided to just continue using the BoringButPractical stick or box magazines instead; a soldier might only have 30 rounds in the magazine, but at least they won't need dozens of extra-large pockets to carry the spares.
* The 10mm Auto pistol cartridge was designed by Jeff Cooper to get the best of the flat trajectory of the 9mm with stopping power on the level of the .45 ACP, and was further scaled up in production. What resulted was a semiautomatic pistol cartridge that delivered more energy than a .357 Magnum. It proved to be overkill, with cartridge cases too long and with too much recoil for comfortable and effective handling and shooting by many shooters, as well as being overpowered for defensive use (where overpenetration is an issue), and so was redesigned into the .40 S&W. It still exists in the 21st century for those who insist on having that level of performance (despite the relative scarcity of ammunition options), or for people who need a semiautomatic for potential defense against bears in the wilderness.

[[folder: Unsorted]]
* Fossil fuels. They provide incredible amounts of energy that can be switched on and off almost at will and the technology for finding and processing them are becoming ever more efficient, but they can be easily hoarded by a few countries/organizations and produce greenhouse gases as well as other pollutants (depending on the exact details of combustion). And once the current supply runs out, it will take millions of years for new deposits to be ready for production.
* In the animal kingdom, being bigger. True, having more body mass and thus being stronger, tougher and more imposing will leave very few predators able to take you on, but even they will be an afterthought when your main enemy is the SquareCubeLaw. Moving around a huge body (or heck, even just pumping your blood around it while standing still) will require enormous amounts of energy, forcing you to constantly be on the lookout for food and consequently all but forcing you to be a herbivore, since hunting would burn more calories than you'd spend chasing or fighting prey. And even if you do find your niche in the food chain, even a slight alteration of the ecosystem can have a dramatic impact on your ability to sustain yourself, meaning you will have far less chances of surviving than smaller but more adaptable species.
* {{Rube Goldberg Device}}s.
* [[MouthfulOfPi Memorizing pi to a large number of decimal places]]. Just 42 digits is accurate enough to calculate the circumference of the sun given its diameter to within the width of ''a proton''.
* Ramune bottles may look cool... but you can't close them again after opening them, which is pretty impractical for a soda. They add a lot to the cost. There are [[http://confectionery.jp/kasi/4902179007292.jpg aluminum ramune bottles]] (which are awesome and not impractical) where the drink itself costs much less [[SesquipedalianLoquaciousness per unit]] [[LampshadeHanging of volume]].
* [[http://www.cracked.com/blog/the-10-year-olds-guide-to-fighting/ This]] Cracked article lays it down in the first entry; ask a kid about fighting sometime, and he'll tell you that 90% of a fight is being able to generate enough raw hell-yeah to make your opponent shit his pants with the force of a cannon.
* This is what the Japanese "art" of [[http://en.wikipedia.org/wiki/Chindogu chindogu]] is all about. Essentially, chindogu are makeshift inventions that seem ideal for solving common problems but are so impractical, create so many new problems, or are just plain embarrassing to use that they're almost entirely useless. One such example is the Butterstick, which is butter in a glue stick form. It allows you to put butter on food without dirtying a knife, but it doesn't work well with soft food such as bread, or small items such as peas. It is practical when serving corn on the cob, though.
* [[http://www.youtube.com/watch?v=TSU1jQoGIqo The machete slingshot.]]
* [[http://www.youtube.com/watch?v=HqIMk__Gxko The Dalek car.]]
* The [[http://en.wikipedia.org/wiki/Energia Energia]] rocket, developed in the late 1970s-1980s in the Soviet Union, turned out to be this. The most powerful launch system ever built, and intended to be entirely reusable in its second incarnation, it actually worked -- but it was ''too'' powerful: the projects it was envisioned for, chief among them ''Buran'', the Soviet space shuttle, and eventually a lunar expedition, got axed by TheGreatPoliticsMessUp that happened just as the system was reaching its full capacity, and TheNewRussia didn't have the funds to run it. As it later turned out, the project was so ambitious that even the US would have had a hard time finding funding. Naturally (and sadly), the project was cancelled.
* Certain synthesizer patches, specifically ones that provide very unmusical effects like engine noises. Sure, they're fun to play around with, but no musician would seriously consider using them in his/her work.
** Unless you're [[Series/TopGear James May]].
* [[http://www.youtube.com/watch?v=JcniyQYFU6M These]] ketchup-squirting robots.
* {{Alcubierre Drive}}s, physically viable idea for [[FasterThanLightTravel FTL]] travel, it's basically a warp drive; it's only insanely expensive, requires an absurd amount of fuel, and has the added [[SarcasmMode benefit]] of creating a large [[BlackHoles black hole]] at the area it's turned on every time it's used. Oh, and the area it moves reaches preposterously high temperatures in transit.
** The other problem is that it'd require more energy than the entire mass of the universe converted into energy all at once to turn one on...Plus you can't steer while it's active, and you can't turn it off easily.
*** Actually, it seems [[http://www.wired.com/wiredscience/2012/09/warp-drive-plausible/ the power requirements aren't nearly immense.]] The other two points still stand, as does one other point that came up in a critique of Alcubierre's original theory: The bubble on its own ''doesn't provide any motive power''. So even if we get an Alcubierre drive up and running, we still have the issue of moving it!
*** Also, the warp bubble is causally uncoupled from the interior. That means that you can't turn it off, which is less a drawback than it might sound because it also means you can't turn it on in the first place. And further reconsideration of the Alcubierre metric indication that it can't actually generate FTL speeds, only go arbitrarily close to c.
* The Bosozoku style of vehicle modification. Whether the end results are classifiable as "awesome" is open to debate, but they are certainly [[http://pinktentacle.com/2010/07/bosozoku-style-rides/ flashy, creative and attention-grabbing]]. They're also horribly troublesome to drive, aerodynamically disastrous and just too unfeasible to use as anything other than show pieces. Good luck handling speed bumps and on-ramps.
* [[http://www.necomimi.com/ Necomimi]] ears are cat ears that move in response to your forehead muscles, and while they look cute, they'll run you at least 100 USD. They can also, as a promotional video shows, completely ruin a pokerface should you wear one while playing cards.
* In the world of NERF and NERF knock-offs, NERF shotguns. On one hand, shotguns are awesome. On the other hand, they shoot two standard shots, when most guns can hold 3-12 times that many, before reloading. And the kinds that use shells, like the Buzz Bee Double Shot, look really cool but take forever to reset the shells. This doesn't include other blasters that are primed in shotgun fashion such as the Alpha Trooper and Rampage, ShotgunsAreJustBetter in that case.
** The NERF Sledgefire, a new addition in the [=ZombieStrike=] line, uses three-dart shells that eject when the breech is opened. Cool, but it can only hold up to 4 at a time, and only comes with 3 since a fourth one makes reloading even more cumbersome. Refilling the shells take about as much time each as swapping out a clip from an N-Strike blaster.
** In terms of cost, the NERF Cam ECS-12, a neat integration of a camera and blaster in one but at somewhere around $80 with a camera around 0.3 MP and 20 FPS, it's cheaper just to strap a [=GoPro=] to a Stryfe or use your iPhone attached to a blaster by an official holder.
*** Not to mention, the Cam ECS-12's microphone is essentially right on top of the flywheel motor, so the only thing you will hear in a recording from it when it's ready to shoot is '''"WHIRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR"'''.
* Some animals end up getting stuck with this as part of their evolutionary adaptation, with the best example being the extinct saber toothed cat. A muscular big cat with elongated banana-sized teeth jutting out of its front jaw must have been the ultimate badass right? Well...evidence has shown that those impressive canines were less fearsome than they appear. While it did help in killing large animals, said animals had to be held still by the cat's prodigious strength to prevent their delicate teeth from breaking from the strain of struggling prey, unlike the teeth of today's big cats which are more durable.
* Fountain pens. They look cool and require less pressure to write with, but also need to be held at a very specific and uncomfortable angle or else the result is a mess of missing ink, on top of being expensive. It gets worse depending on your writing hand; if you're left-handed, you can't write in LTR languages as your pinkie will smudge the ink everywhere, and for the same reason you're screwed if you're right-handed and trying to use RTL languages. It's for these reasons that the far-more-convenient ballpoint pen has replaced the fountain pen in modern ages. It takes some particular skill and need (e.g. professional-level writing) to make fountain pens more useful than, say, a high-end gel pen.
** Can be an aversion if the user has arthritis or other joint issues that make using a ballpoint uncomfortable.
** Really, most ballpoint pens that require refilling. Why bother buying refills from office suppliers when you can buy a cheap biro in any corner shop for half nothing?
* Most of the so-called 'fashionable' haircuts. As [[https://s-media-cache-ak0.pinimg.com/originals/fa/32/51/fa3251a296c467961fc0f5676a836fdd.jpg amazing]] as [[http://www.verstylehouse.co.uk/wp-content/uploads/2014/08/New-Modish-Party-Hairstyle-Collection-2014-15-For-Women%E2%80%99s-4.jpg some]] of them may look, majority of them are absolutely impractical. They generally take a large amount of time to get just right, with the payoff not being as great as the effort, since most people are not up and about long enough to hold this hairstyle for more than 12 hours, tops. And most include touch-ups over the course of the day. There's also the fact that they are just plain impeding in everyday life, particularly those that involve limiting one's vision by a large percentage.
* Creator/AntarcticPress released a series of books on how to draw manga in the early 2000s. One installment focused on swords and pointed out that the ridiculously-designed fantasy swords with wild blades, skulls and encrusted jewels was only good for mantelpiece displays, would only work well as a weapon of VERY last resort, would probably hurt ''you'' more than the target and [[ArsonMurderAndJaywalking you'd just end up trying to copy]] [[WesternAnimation/ThunderCats the Sword of Omens, anyway.]].
** Giant flags (e.g. for [[Webcomic/AxisPowersHetalia Hetalia]] cosplays) have the additional challenge of making sure to treat the flag with respect at all times. The act of setting a flag on the ground or tying it around your body can be seen as disrespectful, even if you're doing it just because you're simply tired of carrying it around. In fact, some conventions even have rules against doing such things.
* Banked-track UsefulNotes/RollerDerby is a lot of fun. It's faster-paced than flat-track roller derby, lends itself to a more wide-open play style, and has tighter scores. The problem is the track itself, which is large, heavy, expensive to maintain, and costly to store. There is a reason why flat-track derby, which can be played on any smooth flat surface that can take tape, is the dominant style of the sport.
* [[https://en.wikipedia.org/wiki/Sexual_selection Sexual display characteristics]] were an attempt by nature to reconstruct this trope. Large peacocks are poor fliers and maned lions are poor hunters, just to name a few, but females find them desirable regardless, because the only way to grow your flashy display is to be one of the healthiest, most genetically stable bachelors around.
** This also applies to humans, of course. Most of the sexually desirable attributes of both men and women offer us no actual advantages in survival, and in many cases are actively detrimental -- for instance, broad shoulders in males and wide hips in females are ungainly, and biologists have been unable to distinguish any functional purpose for the fat stores in a woman's breasts other than sex appeal (ostensibly to simulate being engorged with milk and therefore a more suitable mate). As most women know, large breasts are uncomfortable on the lower back, don't hold their appealing shape forever, and get in the way of lots of recreational activities (even the... obvious one).
* The Dremel Motosaw is an awesome-looking cross between a coping saw and a scroll saw, but while the concept is good, in practice it's awkward to use. First, there is no tension control system, meaning that, unlike normal scroll saws, the blade is prone to bend and break even with thin sheets of wood. As a scroll saw, the working surface is too small and the on/off switch is located in an unconfortable spot, and as a coping saw, it's hard to control due to the stilted handle. With the standard price of $129, plus the replacement blades, it would be wiser to either buy a similar-priced larger scroll saw (or a cheaper one), or sticking with your plain old coping saw.
* UsefulNotes/{{Montreal}}'s Olympic Stadium. Designed to be the world's first retractable roof stadium and the showpiece of the 1976 Summer Olympics, the stadium wasn't fully completed in time for the Games, due to a construction workers' strike. The inclined tower designed to support the roof wasn't completed until over a decade after the Olympics. When the roof was finally installed, it was intended to work like a giant umbrella, with the roof going up into the tower; however, this presented some design flaws. Despite being made of Kevlar[[note]]the same material bulletproof vests are made from[[/note]], the roof was prone to tearing in high winds (and couldn't be operated when wind speed was above 25 mph (40 km/h)) and would often leak water. After ten years, the "retractable" roof was replaced with a fixed roof; however, problems persisted as the stadium is rendered unusable during the winter after the new roof collapsed in its first winter of use after heavy snowfall. After construction delays, mounting interest payments, and failed attempts to fix its design flaws, the Olympic Stadium cost the city of Montreal and the Quebec provincial government over C$1.5 billion, a debt that wasn't fully paid off until ''three decades'' after the Olympics. And it still suffers from structural problems and accoustics so bad that you can't hear anything on the loudspeaker unless you are sitting directly beneath it.
** Perhaps the [[DethroningMomentOfSuck crowning touch]] is the stadium's integration with the Pie-IX Metro station. Being able to walk from Metro to the lower level of the stadium is surely appreciated on rainy days. Less appreciated is the Metro line's position ''directly beneath'' the stadium. This renders the stadium simultaneously too expensive to use and too expensive to demolish because it can't be imploded without destroying the Metro tunnels in the process.
* [[https://en.wikipedia.org/wiki/Personal_rapid_transit Personal rapid transit]] it might sound nice, combining the advantages of cars (spacious individual cabins that can get you anywhere) with those of rapid transit (lower costs, better utilization of infrastructure), they instead combine their disadvantages. They can be as dirty and limited in network size as the [[SubwaysSuck suckiest subways]] and as inefficient in actually handing peak demand in big cities as cars. There is a reason why only four systems exist in the whole world. There are more monorails than PRT systems. And Monorails are (at least in part) an example of this trope as well.
* Considering that most commercially viable forms of nuclear energy only utilize the U235, which is about 0.7% percent of naturally occurring Uranium and the vast majority of the 99.3% U238 are rather expensive waste,[[labelnote: nuclear Physics and economic background]]While U235 splits into several parts when hit by a neutron and releases neutrons fast enough to split further U235 in the process the neutrons released by splitting U238 can't split further U238. However, in any nuclear reactor a small amount of U238 is more or less by chance turned into usable isotopes of Plutonium which can either be used for nuclear bombs or fuel other types of nuclear reactor. For that, the Plutonium and leftover U235 would have to be separated from the waste, for which there are a grand total of two large scale factories in the world (trying to build one has cost more than one government reelection). Another option is modifying the process to produce more Plutonium which is done in so called "breeder" reactors. However, due to the fact that Plutonium is ''very'' poisonous and can be used for nuclear bombs there are understandable political hurdles to large scale Plutonium production. To add insult to injury at current Uranium prices neither breeder reactors nor "recycling" spent fuel are economically efficient[[/labelnote]] technologies that do something useful with the U238 sound rather tempting. However, due to myriad political and economic factors none of those processes has found widespread adoption even though the technological details are mostly figured out. The same goes even more for Thorium, which is three times more common than Uranium, but has to be "bred" first to make useful fuel out of it making it prohibitively expensive at current Uranium prices.
* Most forms of pornography tend to fall here, as the depictions of sex within tend to emphasise what looks good and heightens the sexual fantasy of the viewer over the practical mechanics of sexual intercourse. As many performers have discussed, "porn sex" is shot to look exotic and exciting but actually tends to be rather awkward and uncomfortable for the people involved and, depending on the act in question, may require lengthy (and at times rather gross) preparation to be safe and hygienic for those involved. Consequently, it tends to be less useful for the purposes of enjoyable love-making than straightforward "vanilla" sex would be.