->''"There's also a guy with a unique sprite there. So you know what THAT means."''
->-- Chibi Soma's ''MegamanBattleNetwork 5'' walkthrough

''Every detail given is important.''

We have 42 minutes. If we give a detail, it better be important.

Oh, sure, we can set up a RedHerring or so, but we had better expect the viewer to attach importance to any detail we let loose in the plot. Shame on us, if we later expect the viewer to be surprised by the importance of the detail we let slip.

Although conservation of detail tends to be particularly pronounced in a "compressed" medium like a weekly television show, it ''is'' a proper and useful tool for creating fiction in all media, filtering out irrelevant detail to make time for actual plot. Keep in mind that unwarranted detail is generally poor writing, and will only make your audience wonder WhatHappenedToTheMouse. There's a fine line between good WorldBuilding, and rambling on about pointless crap, just as there is a difference between good description, and PurpleProse.

"How come people on TV always find a parking spot right outside their destination?" This is why.

The law can also be applied to video games as well. If any particular detail of the game requires a significant investment of time to develop, it will always be a primary detail. One-off [=NPCs=] rarely ever get anything more than a [[OnlySixFaces generic sprite/character model]], given only the most basic walking animations, and have [[NominalImportance no name]]. You can tell that a character will play some role in the plot when they have an unusually complex character model (or, specially in 2D games, a headshot on their dialog). Plotwise, this serves to separate [[RoundCharacter Round]] and {{Flat Character}}s.

This trope has probably caused more EpilepticTrees than every other trope combined (DyingDream notwithstanding), as people ''expect'' things to have a reason.

When the audience is put off by giving a reason, only for the thing to return and prove important in a different manner, use, etc., the writers have used ChekhovsBoomerang. The predominant use of ChekhovsBoomerang is to let the writers surprise you when you are expecting things to have reason to be there.

See also ChekhovsGun, ChekhovsGunman, [=~Olaf's Hammer~=]. Contrast NamelessNarrative.
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!!Examples

[[foldercontrol]]

[[folder: Film ]]

*Parodied in ''KissKissBangBang'', when the narrator sarcastically points out the importance of a conversation in his story.
-->'''Harry:''' ''"I’m so sorry. That was a terrible scene. It’s like, why was that in the movie? You think it’ll come back later? Hmmm..."''
*Used very well in ''BackToTheFuture'', which disguised its plot points as jokes.
* Used to create tension in the final battle of ''Film/IronMan''. When Tony creates his original power generator, he observes that it could run "something big for 15 minutes." [[spoiler: When he is forced to use his original generator after Stane steals his improved model, there is a literal deadline for Iron Man -- if he does not beat Ironmonger in less than 15 minutes, he will run out of power ''and'' his heart will stop.]]
** Also, the "icing problem."
* Chris Farley's unusually knowledgeable security guard in ''[[WaynesWorld Wayne's World]]''.
* Near the beginning of ''[[{{Film/Spider-Man}} Spider-Man 3]]'', Peter reassures Mary Jane about her singing's audibility by expositing about acoustics. Mary Jane dismisses this as (a) Peter trying to comfort her, and (b) Peter being a nerd. However, in the climactic battle [[spoiler: it is precisely this knowledge of acoustics that allows Peter to defeat Venom.]]
** Actually, the key to victory was Peter's observation that Venom freaked out whenever something large and metallic went "clang". His knowledge of theater acoustics had nothing to do with it.
* ''TheIncredibles'': the ''moment'' Edna Mode starts making a big deal about capes being caught in things, you know that someone else is going to experience a very fatal wardrobe malfunction by movie's end.
* Playing with this trope is arguably the main conceit of [[CitizenKane Citizen Kane]]: it's a movie about the impossibility of finding the right details. "Rosebud" is an example, as is the famous "girl in the white dress" speech.

[[/folder]]

[[folder: Anime and Manga ]]

* Subverted in the second episode of ''DeathNote'', Light spends a good chunk of the episode setting up and explaining an elaborate safety mechanism to hide his notebook, and it never comes up again. Instead, the pay-off is more immediate: it gives the audience a quick introduction to Light's personality.
** In the manga, when he notices that someone (the people who installed the cameras) entered his room from the state of his no less elaborate door safety mechanism, he infers that they didn't find the notebook because the fire trap didn't go off.
* Double Subverted in the ''{{Mai-HiME}}'' anime. This troper's immediate thought when Mai first encountered [[YouGottaHaveBlueHair blue/white haired]] Miyu was a sarcastic "She's not important at ''all.''" Subverted in that the scenes that appear to foreshadow this instead turn out to be all about Akane, the relatively plain-looking brown-haired girl. Double subverted in that as soon as Akane has her moment, Miyu shows up to provide the "Wham" in WhamEpisode.
*Football manga {{Eyeshield 21}} does this with every team the main characters go up against. Except for the protagonist's team, every team consists of a few dozen generic nameless players (whose faces are usually hidden behind their helmets) and two or three important named characters (who are inevitably the stars who make all the big plays.)
**You can tell how important a team will be to the story by how many players get names; the first team they play, for example, gets one named player, and after that game they never impact the plot again. Meanwhile, important recurring rival teams get five or six named players, plus coaching staff.

[[/folder]]

[[folder: Literature ]]

* In Jasper Fforde's ''[[ThursdayNext Something Rotten]]'', Thursday is showing Hamlet around the "real world" when she is almost injured/killed by a random accident. She explains to him that, while in the Book World (fiction), this would certainly turn out to be an important clue to something later on, in the real world, such events are meaningless. Of course, because ''Something Rotten'' is fictional, it does turn out to be an important clue to something later on.
** The ''ThursdayNext'' books are intentional parody of literature and literary tropes. I mean, "and a shot rang out" was a glass ball until it fell, shattered on the floor, and a shot rang out and everyone turned to see who fired it (''Well of Lost Plots'').
* In ''[[{{Belgariad}} The Belgariad]]'' by DavidEddings
** In the historical-perspective prologues of the very first book, ''Pawn of Prophecy'', mention [[spoiler:the High Places of Korim, which are no more]] in passing as the location Torak did some stuff... only for [[spoiler:it to be the solution to one of the last mysteries of the sequel series ''The Malloreon'']] literally ''ten books later.''
** At the beginning of ''Pawn of Prophecy'', the first book, the old storyteller brings out [[spoiler: a story only to be told in the presence of royalty, even though he's in an ordinary (though pretty wonderful) farm, and glances at Garion]]. Lo and behold, halfway through the fourth book [[spoiler: Garion is crowned the Rivan King.]] Of course, the old storyteller, being Belgarath himself, knew the entire time.
** Also in ''Pawn of Prophecy'', Garion mentions to Belgarath in a throwaway line that [[spoiler:a fortuneteller once came to Faldor's farm and told Durnik the blacksmith that he would die twice]]. Funnily enough, in book five, [[spoiler:Durnik dies and is resurrected a chapter or two later. One down, one to go.]].
* Averted in ''AmericanPsycho'': there is lots and lots of detail on music, fashion and food, all of it plot-irrelevant.
** That book doesn't really have a plot anyway.
*Lots of "masterful" literary works (James Joyce, I'm looking at you) are called so due to complete aversion of this trope. The lady passing on the street is described in extreme detail and is never seen again.
* If someone is invited to a banquet in ''RomanceOfTheThreeKingdoms'', then chances are that it's part of a plan to kill them. Most of the banquets without murderous intent go unmentioned, leaving modern readers to wonder why anyone would be stupid enough to go to a banquet in the first place.
* DouglasAdams is famous for mentioning things in throwaway lines which later turn out to be what the entire plot hinges on. However, he does a ''fantastic'' subversion in ''Dirk Gently's Holistic Detective Agency'' (which is itself an entire ''book'' of this trope) - there's a scene where the protagonist is looking into a bathroom, and Adams spends several paragraphs describing the contents of the room, the panelling on the walls, the scuffs on the floor, and so forth, in intricate detail, only to end with "There was also a large horse in the room, taking up most of it."
* Subverted in the book series ''PersonalEffects.'' The main gimmick of the series is that it encourages the reader to follow up on details mentioned in the books - calling the phone numbers gives you voicemails, and all the websites actually exist. The first printed book even comes packaged with a bunch of handwritten notes and pictures.
* ThisTroper had trouble with [[TvtropesWillRuinYourLife this trope]] in ''TheDresdenFiles'' novel ''Turn Coat''. We know Harry is looking for a traitor inside of the White Council and [[spoiler:Wizard Peabody is a background character who appears once in the previous book, and is not given any detail at all. Suddenly, in ''Turn Coat'', he's described, given lines, his job is explained, and many scenes plainly have him there so we can see how he interacts with some of the people we assume could be the traitor. This all happens even before Harry gathers any real evidence. And it turns out that yes, Peabody is the traitor.]].
** In actual fact, [[spoiler:Wizard Peabody has been a recurring minor character since ''Summer Knight'', and has had pretty much the same role in all his appearances, and noted to be fairly indespensable. Given that Peabody is based at White Council HQ in Edinburgh, and ''Turn Coat'' is Harry's first "on-screen" trip there, it makes sense that Harry encounters him so often.]] That said, this troper did find it slightly suspicious as well, although not to the degree shown in the reveal. [[spoiler:This troper originally suspected the Merlin was the traitor.]] Boy was I wrong...
*** There were TWO enemy wizards at the battle. So...............
* ''HarryPotter'' author J.K. Rowling inadvertently bit herself in the rear because of this once. In ''[[{{HarryPotter/HarryPotterAndTheOrderOfThePhoenix}} Harry Potter and the Order of the Phoenix]]'', Harry refers to a Muggle boy named Mark Evans while arguing with Dudley. Because of Rowling's use of this trope to mention in passing characters that would be important later and the fact that "Evans" is Lily Potter's maiden name, fans jumped on this believing Mark Evans might be some long-lost relative. No. Rowling just made a mistake.
** A mistake? With the huge number of people in the world, almost all people have someone who shares their last name despite having little or no relation due to sheer chance. A justified breaking of the OneSteveLimit, and a case of the ''fans'' being too GenreSavvy for their own good.
*** Still, Rowling felt the need to apologize. (She's nothing if not polite.)

[[/folder]]

[[folder: Live Action TV ]]

*Parodied on the DVD commentary for the final episode of ''TheOffice'' (UK). Gervais and Merchant lampshade the "Secret Santa" game, commenting on its apparent insignificance to the plot, and how it ''definitely'' won't become relevant later.
* In an episode of ''{{Charmed}}'' Prue finishes talking with someone in her office, that person leaves and then the coffee girl (who we've never seen before) arrives, gives her coffee which had apparently been ordered, receives a compliment, and the scene ends. Yeah. The feeling "why did they just show us a scene of someone receiving coffee" was pretty strong, but it did help remember the coffee/sandwich girl character for when it turned out that, without her knowledge, she was actually [[spoiler: the mother of the person who will eventually find a vaccine for [[spoiler: demons]].
* Played straight during an entire series of ''StarTrekDeepSpaceNine'' regarding the Dominion, which was mentioned in passing in the first episode it showed up in and [[spoiler: was on the verge of taking over the Federation a few seasons later.]]
* In one episode of ''{{Goosebumps}}'' we see the parents of a kid protagonist working on something. It turns out [[spoiler: it was a device to expose invisible people and the plot had an invisible friend]].
* Used judiciously on ''{{Monk}}''. Just about every single random detail comes into use. Character pronounces a word differently? Clue. Has only an aunt for family? Clue. Orange juice jug empty? Clue. Bike comes with a lock? Clue.
* A fan theory regarding the identity of the mother on ''HowIMetYourMother'' relies on this trope. In season 3, Ted [[spoiler: literally bumps into a girl at a party that he reveals the mother was at. The scene is at most 3 seconds. Ergo, due to conservation of detail, she is the mother.]]
* ''{{Seinfeld}}'' did the opposite and focused on silly things(like the parking spots mentioned above), yet it was still funny. ''Curb Your Enthusiasm'' after it, however, was completely made up of small details and barely had anything else, which is why it is awesome.

[[/folder]]

[[folder: Tabletop Games ]]

* A very common mistake for new {{Dungeon Master}}s who will vaguely describe a room, but go into minute detail about one feature of the room. All GenreSavvy players will immediately gravitate towards this item.
** This can also be [[DangerouslyGenreSavvy used]] [[PaintingTheFourthWall intentionally]], by only describing a certain part of, or item in the area, you can [[EnforcedMethodActing ensure that]] [[SchmuckBait everyone notices it]].
* One RPG group went by the tenet that 'Any woman or plant the GM bothers to describe is a trap.' The GM caught on and ran them through an adventure that could roughly be described as 'The Magic Greenhouse Land of Amazons'.
* Similarly, whenever the DM makes a hidden roll or asks for a spot or listen check (that they fail), the players will assume something is going on and, if they're bad metagamers, try to act on it. This troper DM took up the practice of rolling randomly or asking for spot checks when least expected, just so the players wouldn't know when the relevant rolls were made. Incidentally, few things unnerve a player as much as rolling really well on a spot check and being told, "No, you don't see anything of importance..."
** Especially when the players then use Karma Points (or similar, depending on the game) to bump up the roll!
***In those cases, it's time for SchrodingersGun! Oh look, there ''is'' something important!
** Paranoia recommends that GMs occasionally roll the dice for no reason other than making the players nervous.

[[/folder]]

[[folder: Webcomics ]]

*In ''ElGoonishShive'' the author had intended for a one off character(the principal of a school specificaly) to have a massive scar and eyepatch. Due to this law he chose not to since he had no explanation planned for them.

[[/folder]]

[[folder: Video Games ]]

* Subverted with Ziegfried in ''FinalFantasyVI''; the character is interesting and appears throughout the game, but is completely unimportant. This characteristic has its own entry on TheGrandListOfConsoleRolePlayingGameCliches:
-->'''Ziegfried's Contradiction:''' Just because someone is weird doesn't mean they're important.
*Subverted in ''SuikodenII''. There's a character with a name and portrait but she isn't important to the story at all.
** She has a portrait and name (Eilie) for one reason. In the quest that's unlocked if you load SuikodenI data at the start of the game, [[spoiler:Tir [=McDohl=] joins your party while Gremio occupies a Convoy space. However, if you failed to resurrect Gremio in the S1 file you loaded, he'll be dead in this game, and Eilie will take his place in the plot, occupying the convoy and speaking his lines instead]].
*Subverted in ''ChronoCross''. Of the portraits that characters have, 40 of them are playable characters, 5 of them are alternate versions of the playable characters, and 26 of them are NPCs. Of the NPCs, one is unimportant: a shopkeeper you meet early on. Throughout the game you become convinced she'll be important, but she never does, being the only one of the LoadsAndLoadsOfCharacters who isn't.
* Avoided in ''MetalGear'', ''{{Snatcher}}'', ''{{Policenauts}}'' and just about anything HideoKojima does, because of his ''total and freaking obsessive-compulsive insanity''. He cannot stand to ''not'' worldbuild. Pretty much the only people who care about the incredibly elaborate [[DeusAngstMachina tragic backstories]], sex lives and namedropping pertaining to characters who show up once and then die - not to mention the endless infodumps about guns and items and nuclear weapons and the future and useless metagame trivia - are going to be fanfiction writers. For the most part, backstory events will be mentioned inconsequentially to add a little flavour to a character.
** Hey you have to respect a man who puts in that much work. And at least in ''MetalGearSolid'' Kojima-san was nice enough to let players skip all that and go right to the neck-snapping if they want.
* The entire ''AceAttorney'' scene is all over this, up to the point of being {{Anvilicious}}. Every piece of evidence - besides the lawyer's badge, etc. - is always used at least once. The problem is using the right one, because you need to use them [[GuideDangIt as a sort of sentence fragment to answer questions.]]
** This can get to the ridiculous extent of saving before a particular point you don't know how to get through, and just trying out ''every single item''.
*** And profiles, in ''Justice for All'' and ''Trials & Tribulations.''
* One Sega CD role playing game would say things like "Who would talk to a cow" if you talked to the cow, as all role players will do. Also mentioned "Wow the guards and castle are laid out exactly the same in this castle as they were in the last one. Maybe that is to show how the two kindgoms are very closely tied, or maybe the programmers were just lazy."
*Near the beginning of ''TheLegendOfZeldaMajorasMask'' we find a masked character that ''manually'' opens doors unlike every other NPC in the entire game. This tiny fact foreshadows just how long his particular sidequest will go on for and how much of an NPC he really is...
**ThisTroper just chalked that up to Kafei being the same size as Link, and therefore being able to use Link's animations without it looking weird.
* Subverted in ''MegaManZX Advent'' due to its attempts to avert YouAllLookFamiliar, where pretty much everyone you meet has different designs and personalities, except for the guys in uniform, who still act different. In other words, trying to rely on this trope to see who is important is completely pointless for this game.
* ''AceCombat 04: Shattered Skies'' mission "Deep Strike" is set in an area with a ravine leading from the target area back to the RTB line. After splashing the targets, you get notice that Stonehenge is firing your way and have to take your plane below 2000 feet in order to make it out of the area. The only way to do that? Why, the ravine of course. It also shows up in the "Megalith" mission. Those other missiles within reach aren't just for show.
* In ''Fire Emblem'', almost all enemy or NPC with unique sprites and more then a few lines of dialogue is either a boss or recruitable. Which is understandable, considering how many enemies you end up facing.

[[/folder]]

[[folder: Real Life ]]

* It's a widespread belief among students that, on true-false exams, any particularly long statement will be true. The idea is that the teacher wouldn't go to the trouble of composing a detailed ''false'' statement.
** Can we start getting TroperTales of this last one? This Troper has been fooled that way before...
** This troper took the opposite view. Higher chance of a PlotHole, er... error, that you could argue in your favor if it did turn out to be true. Curse college profs to be smart enough to usually add "best" answer instead of correct.
*** This troper has found that, on multiple choice questions, the longer answer often IS the correct one, as long as it isn't blatantly stupid. It's not always correct, but it's useful for hazarding a guess if you really don't know the answer.
**** This trope has aced several tests he knew nothing about this way.
**** It is actually a studied idea that True False tests will have more true then false because the teacher wants students to be right, thus the false have longer information to ensure they look "wrong".
***** Same can be said for "All of the Above" because again, teachers generally test what the student knows and as such wants success.
*** It depends on how smart/evil the teacher is, TheBadWolf I have had teachers that loved really long statements that concealed subtle flaws in them.
*** Perhaps it is worth adding that lies are often made more elaborate than the truth, simply because they're intended to sound convincing.
*** After all, fiction has to make sense. Reality has no such restriction.
*** In my experience, if there are multiple choice-answers, and most of them do NOT have an "all of the above" option, for the rare ones that do have it, it inevitably is the correct one.
***In engineering school, you can probably assume that absolute answers on true-false exams are wrong and hedged answers are correct. With the exception of entropy increasing, there are no absolutes in engineering to to lack of further information.
*** This troper's economics teacher in high school always used the same structure for multiple choice questions. Out of the four answers, one would be completely different from the others and always be wrong. Of the remaining three, only one would have something in common with the remaining two, making that the right answer. So if C is completely different, and B has something in common with A and D, but A and D have nothing in common with each other, B is always the right answer. Every question worked that way, you honestly ''never'' needed to study for his multiple choice exams.
**** You know, if a subject depends more on pattern recognition than rote memorization, this kind of approach ''isn't even cheating''.
*** It is, in fact, very difficult to construct good "guess-proof" multiple-choice or true-false exams, which is why this troper at any rate has difficulty understanding why anyone would use them in the first place, unless it's to aid automatic marking. Not only is it easy for an inexperienced setter to fall into traps like the one described above, but it's also usually easy for examinees to justify answers other than the supposedly correct one or indeed to declare that all provided answers are wrong.
***This troper once had a multiple-choice exam. All the correct answers were "A". It really messes up with your mind when you write down your 15th "A", you start to doubt everything.
****In this troper's case, every answer was "C". There's probably some way that such a test should qualify as psychological warfare.
*****Well, yes, my psychology teacher tried this and watched the utter lulz unfold.
***The Freakonomics blog wrote a column related to this about how one could use game theory to try and figure out the correct answer to a multiple choice question by reading only the answers and not the question itself [[http://freakonomics.blogs.nytimes.com/2008/12/18/the-art-of-satergy here]].
***This troper once overlooked an anecdote related to Kellogg's cornflakes in a psychopahology textbook because no real University professor would be petty enough to throw in a question about a minor historical fact in a third year course's final exam just to check if the students read the book when he could be asking about the various manifestations of schizophrenia, right?
* Common among MMO forums, at least by the fan base, such that almost anything a developer says will usually be taken as absolute fact (or lie) and obsessed over for every possible meaning. Even if the developer is simply being chatty about nothing.
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