A subtrope of Informed Attribute: A character's skill and abilities are frequently mentioned by the cast, but are nonexistent in practice.
Though the motivations for allowing this are similar to the motivations for allowing Informed Attributes in general, there is much less of an excuse for it. Believably getting it across that, say, someone is compassionate is difficult stuff; it's the mark of a good author to pull that kind of thing off. Skills and abilities are a much simpler deal: Is someone a master locksmith? Have them pick a lock now and then. Are they combat experts? Have them take the fight to their opponents whenever they can and gain the upper hand.
What often deters writers from going through with the above plan is the fact that, well, Most Writers Are Writers. They're writing a character who's supposed to be a musician, but they don't know the particulars of meters or chords. They have a character who is a military expert, but they don't know how long an infantry division can fight until it needs to be resupplied. They have a character who's a genius, but they haven't a clue what kind of problem only a genius would be able to work through, or how. If they actually attempt to show the ability in action they take a very real risk of the portrayal falling completely flat.
On occasion, the ability cannot adequately be portrayed by the medium used for the work. For example, a comic book cannot show how good a character's singing voice is, and a radio show would, at best, be forced to merely describe a character's great paintings.
One choice the writer has is to go ahead and show the supposed "ability". But if they don't do the research, this leads to such laughable characters as the scientist who spouts Hollywood Science, the tactician who comes up with the sort of tactics a five-year-old would think of and the "genius" who is only a genius because they're the only one coming up with any plan at all, and everyone else is downright stupid. Lack of convincing detail means the reader does not believe, whether it is fixing an engine or presenting the actual philosophy of a character purported to be wise, and can make the readers long for the informed ability.
It's much easier for the writer to just stay away from showing that character's expertise at all. After all, how can the portrayal possibly live up to the hype? And since the audience has to know about this expertise some way or the other, this inevitably leads to telling the reader about it instead of showing it to them.
There are, fortunately, ways around this.
The easier way is to have the character act out their expertise without going into technical details. The military leader arrives at the war room, going from briefing to briefing, gives out commands over the radio and the tide of battle turns. The master composer comes up with the hook for a popular singer's upcoming single, and a week later we hear that it is topping the charts. The character can display their skills without showing their work directly- it's only an informed ability if there is no meaningful evidence they have it, or, worse, evidence they don't have it at all.
This trope can be Played for Laughs - a character might find increasingly bizarre and unlikely reasons to not use their alleged abilities in situations where they would prove useful, or that one time where they actually put it to use may be a Noodle Incident that goes on being mentioned at random, or they may display their skill, but in a manner conspicuously offscreen while the other characters exclaim "Look at them go!". If they finally, at one point, go ahead and prove that they are every bit as capable as their reputation suggests, that's Let's Get Dangerous.
See also Faux Action Girl, where "competent fighter" becomes an Informed Ability. A Necessary Weasel in Video Games, where often you'll be playing someone supposedly very competent, but how well they actually perform is up to you, and often they'll go through tutorials teaching them the basics of their supposed area of expertise for the player's sake. Compare Character Shilling and compare/contrast with Creator's Pet. Also see The Pirates Who Don't Do Anything, where the characters never even attempt to perform the tasks for which they are supposedly famous.
Note: If the particulars of a character's skills are intentionally hidden from the audience for dramatic effect, but the skill itself does come into play, that's another trope.
In The End of Ends, we're only told of what Copy Cat could do, and outside of his namesake ability to change into anyone he touches, we never see them get used.
Inner Demons: In the follow-up stories and sequels, the reader is told that Vale is exactly the same as Rarity in almost every aspect save her cutie mark. Rarity is a Drama Queen tailor who usually struggles between her greed and her desire to stand with her friends, and ultimately cares for the ponies around her. Vale is a stone-cold serious warrior-goddess who Would Hurt a Child, refuses to go against her "mission", and seems to think murder is the only solution to every damn problem she faces, regardless of whether it makes a situation worse or not.
Fan Fic/Showa&Vampire: The main character's mother is supposed to be one of the greatest authors who ever lived (she writes erotica). She's incredibly famous for her output and most of the "good" characters are fans of her work, none of her prose is ever actually shown.
Tenacious D's "Wonderboy" explains how his rival Young Nastyman has levitation, telekinetic mind bullets, and the power to move you. These powers are explicitly "comparable to Wonderboy". What Wonderboy himself is capable of is a mystery.
"Tribute" parodies this trope, claiming that Tenacious D themselves successfully played "the greatest song in the world" when the devil demanded it, but they can't prove it because they forgot how to play the song.
The Lonely Island song "Sax Man", with guest artist Jack Black boasting of Sax Man as a legendary virtuoso who's been rocking out since he was three weeks old. When Jack prompts Sax Man to play however, all we hear are blowing noises and a bit of discordant tooting.
Mike is supposed to be a brilliant best-selling novelist who sold his first book on his first try with no editing needed. Yet the excerpts from his first novel, as featured in the character's letters, are filled with implausible and maudlin situations, and insightful lines like "The living buried the dead."
Liz's parents and friends are constantly telling her how successful, smart, funny, and great Anthony is. However, he only got his job through connections, never says anything witty, and isn't even shown at the astronomy club, his only social outlet.
Charlie Brown in Peanuts claims that everyone hates him and he has no friends, even though Schroeder and Linus are clearly his friends, and although Lucy insults him, she also hangs around with him an awful lot. Also, all the neighborhood kids let him be manager and captain of the baseball team. Of course, this makes more sense when you know that the creator Charles M. Schulz, even when he had a wife, five children, and millions of fans, still complained of being anxious and lonely. On the other hand, sometimes even Linus and Schroeder belittle him, and not in a Vitriolic Best Buds way. It's also been stated in the strip that Charlie Brown is the manager of the team because he's the only person who really cares about it that much (to the extent that he'd rather manage than eat).
Dennis The Menace, despite being regarded as such by his parents and neighbors, is hardly ever shown misbehaving at all anymore, no doubt due to parents complaining about him being a "bad example" or the fear thereof. But he was a real terror in the early days.
Bart Simpson was created specifically because Matt Groening remembered how disappointed he was with Dennis, and wanted to create one whose trouble making wasn't an Informed Ability.
It got even worse in the Dennis sitcom and cartoon, where the kid wasn't actually allowed to do anything bad. Instead, he was written as an innocent well-meaning lad who always got into trouble by accident. A better title might have been "Dennis the Unlucky." On the other hand, this qualified as Adaptation Distillation to those kids who found the good-natured Dennis to be a much more likable character than the nasty Bratty Half-Pint from the early comics.
In the strip, this is used for comedic effect. Calvin's imaginary alter ego Spaceman Spiff is constantly described as a tremendous pilot, superb marksman and all round brilliant space explorer, but pretty much every story about him begins as his ship is crashing and/or he's captured by aliens. His "Death-Ray Blaster" also tends to be utterly useless, because in real life it's actually a squirt gun. Spaceman Spiff's piloting is also lampshaded in one strip: "The intrepid Spaceman Spiff is stranded on a distant planet! ... our hero ruefully acknowledges that this happens fairly frequently."
Same with Stupendous Man; after yet another blunder, Hobbes asks Calvin if Stupendous Man ever won any battle. Calvin replies they are all "moral victories."
In Dick Tracy, the Iceman is described as being in the top elite of hitmen, has pulled off a dozen killings without even getting a criminal record. No-one is ever a match for Tracy, of course, but even before he encounters Tracy, the first killing that the Iceman is shown commiting is a real amateur affair. He not only leaves his disguise behind where the police easily find it, he allows himself to be seen committing the crime.
Alice is an even stronger example. While Dilbert can lay claim to getting one or two strips per year where he's working on a specific project, Alice has 14 patents and was the highest paid engineer at the workplace but all she ever does on-panel is use her Fist of Death on hapless co-workers.
Often happens when the commentators have to shill a Creator's Pet, and moreso when they're simply trying get a new act "over". Jobbers and journeymen are made to seem like extremely talented athletes all the time — a good example of a Justified Trope in this instance. It's pretty much the announcers' job to do this.
Similarly, wrestlers are often verbally boosted even if they're higher up the rankings. Triple H is a wrestler who was rather good, but not exactly a technical mastermind (he kicked and punched a lot, and stuck to only some basic submissions or wear-down holds). And the extent of his planning was usually "lure opponent down to ringside, then hit with a sledgehammer". The announcers played him up as not only the best technical wrestler alive, but the "Cerebral Assassin", noted for his brilliant planning.
Similarly, although maybe a little more methodical is Randy Orton, who although would be a little unnerving to actually have to deal with, his "psychological torture" of his opponents usually extends as far as extending submissions, moving slowly, hitting them, and giving a few evil-looking stares. Has an evil air, but not exactly a super villain.
Subverted with Hulk Hogan. Commentators often talk about how exceptional he is despite most of his technical performances being average. He actually was, at a minimum, a better than average technical wrestler, which is more obvious if you see his performances when he was less well known. As he became more popular, he dialed down the technical aspect of his performances to minimize the chance of injury. Effectively, the audience was being informed of his technical abilities, which virtually none of them would ever see, despite the fact he was, at least to some extent, a better wrestler than his performances indicated. Maybe not as exceptional as the commentators would have you believe, but good enough that he didn't rely on mic skills as completely as many of his critics would indicate.
Many times, although not always, whenever Wrestling Doesn't Pay come into play, this happens. Most recently, it's fairly obvious that Fandango and his partner Summer Rae simply cannot dance.
Was sadly the issue with Chavo Guerrero. Known within the wrestling community for being extremely talented. Unfortunately, many WWE fans never saw Chavo's true potential as a wrestler. Because he was often made the Butt Monkey of many matches, resulting in them ending because of some outside interference or Chavo, himself, being a Heel, never pressing to win many of his matching, resulting in him holding back most of the time in the ring.
Michael Cole seems to throw out the phrase "Architect of The Shield" in every match regarding Seth Rollins, implying he's the one giving orders and blueprinting the assaults. From what we've seen, Ambrose is the one planning backstage, and Reigns gives orders during the assaults, making this mostly hype from Cole.
This title normally refers to the bit of trivia that the Shield was apparently Rollins' idea, having contacted Ambrose and Reigns about it. This would be fine if not for the fact that this was never alluded to at all until Cole started saying it about a year after the Shield formed.
King Solomon. God grants him the gift of boundless wisdom in a dream that was only witnessed by Solomon himself. The text gives exactly one specific demonstration of this wisdom. He also allegedly wrote three deeply philosophical books of the Bible, but allegedly the aforementioned books contain loanwords from other languages that according to many historians weren't known to the Israelites until centuries later. The Queen of Sheba also found his wisdom appealing enough to make a very lucrative business deal with him, but the text doesn't recount what exactly he told her. Moreover, in his old age he turned his back on God and imported some idols to worship (despite having personally conversed with God more than once), this being one of the gravest sins in the eyes of the ancient Hebrews and a sure way to lose divine favor.
Satan, from The Bible. The New Testament calls him evil a lot, when it mentions him, but it never really shows him doing much of anything evil except in Revelation. It's generally believed that he's the source of all temptation, so it's more a case of your acts being the evil deeds and him being merely the inspiration for them. Subverted in that he did initiate the first rebellion against God's rule, and as The Corrupter, one could legitimately lay at least partial responsibility for every suffering, every death and every act of cruelty and depravity.
Critics of Christianity like to illustrate the supposed evil of Satan using this chart◊.
Freyr in Norse Mythology is said to be a the god of fertility, peace and love. Not that he is actually that peacefull or loving. Most of the myths around him has him as a warroir and has him send his servant to woo a giantess through dubious means.
Happens often in tabletop RPGs, where a character might have a lot of points in charisma, intelligence, or wisdom, but will still be played like a boorish nincompoop because of player incompetence.
In GURPS it's possible to take the advantage "Common Sense" to avoid this. The description says that if you do something outrageously stupid (like having your charismatic rogue urinate in the King's face) the GM has to mention it and let you decide on a different course of action.
Some Dungeons & Dragons rulebooks will discuss this as well - a character may have fantastic intelligence, wisdom, or charisma, but the player will have nothing of the sort. This is inevitable when playing a wizard or cleric, whose intelligence or wisdom is very likely to reach officially superhuman levels. In that case, it's acceptable to just stick with ability checks in lieu of roleplaying. Or a DM can do what many D&D CRPGs do, nudging a mentally-endowed character appropriately toward correct solutions and insights, or warning them away from stupendous mistakes.
Tier-Induced Scrappy classes and races can lead to this. A high level fighter (a low tier class) is described as a warrior without peer, and a truly terrifying sight to behold; the fact that a mid-level caster can probably destroy him from several football fields away will go unremarked upon. Likewise, elves are supposed to be master wizards, using their centuries long lifespans to discover arcane secrets beyond comprehension. In actuality, they have a penalty to a very important stat, and their racial abilities are subpar.
Some Elves tend to fall into this trope in general, especially in D&D, where they're long-lived and said to be masters of magic... except they don't gain EXP any faster than anyone else, they're less free to multiclass and gain fewer skill points than humans of equal intelligence and class levels. Further, although Elves may live in conditions superior to the rest of the world, their cities are often described as having been standing the same way for hundreds of years, implying no technological progress.
Similarly, it is not uncommon for a DM's carefully-grafted primary antagonist, legitimately given godlike statistics and abilities on paper and obviously feared throughout the setting as a bona fide genius bruiser, to go down in a round or two of combat in essentially any tabletop RPG short of Call of Cthulhu, while some of the lead-up encounters intended to be a light warm-up stretch out for hours. This is a natural result of one guy writing the modules being unable to be either as smart or as stupid as 3-7 players putting their heads together, but often FEELS like a bit of an anticlimax.
It is interesting to read the original AD&D Dragonlance adventures and compare them with how the characters act in the novels. Raistlin, the epitome of the sickly Squishy Wizard, is given a Constitution of 10 - perfectly average. He is also described as one of the greatest geniuses that ever lived, and engages in battles of wits with gods and near god-like beings....with his Intelligence of only 17. According to the ruleset at the time, he couldn't even cast the highest level of spells.
The 3rd Edition Forgotten Realms Campaign Setting was absolutely insane in this regard. Since it was made very early in that editions's life cycle, the designers plainly had no idea how to make characters competently. Many were inexpertly converted from their AD&D stats, and it really shows. The most famous examples would probably be Drizzt (CR 18 and supposedly the greatest swordsman of his generation, would probably get killed by a frost giant of half his level) and Elminister (CR 39 and supposedly nearly a god, he's got a whole load of Dead Levels that put him on par with a wizard ten behind). They're far from the worst offenders, though; check out Harper leader Storm Silverhand's unmanageable mess of a build and Scyllua Darkhope, High Captain of Zhentil Keep, frequently outdamaged by her own mount.
Some Ravenloft Modules by their very nature cause Rudolph Van Richten to fall under this trope, considering a good number of the Quests involves the man getting tricked by any number of evil entities far more often than the 'Land's Premier Expert on Undead and Other Evil Horrors' really should be. It takes a skilled GM to not turn Van Richten into an unintentional Miles Gloriosus. Later justified in that he is under a Vistani curse which keeps him alive as everyone he loves dies for most of his life. He disappears shortly after the curse is broken.
Most of the lore you'll run into makes the Space Marines out to be the biggest badasses in the history of ever, but ingame in terms of stats and abilities they're pretty much the baseline army. This is due to both Gameplay and Story Segregation and Power Creep; Space Marines, while nowhere near as overpowered as the fluff make them out to be, are indeed better than the average rank-and-file troops of every other army. This is evident if you compare Warhammer 40k with it's parent game Warhammer Fantasy; the baseline toughness is 3 while the best rank and file armor is usually 5+. This is in contrast to the Chaos Warriors, who are literally Space Marines in all but name (and gun) and considered one of the elite troops. However due to the vast majority of the players playing Space Marines, as well as the subsequent numerous spinoff armies, they became the baseline.
There is a tongue-in-cheek army list Games Workshop created that did have the Marines as powerful as they are in fluff. In a full-size game they could field 6-10 guys depending on equipment, and they are called "Movie Marines" because in-universe this is how they are depicted in propaganda videos.
In Sunday In The Park With George, Act II George is supposed to be an innovative artist (or "inventor-sculptor" as he thinks of himself), but all the audience sees of his artwork is a stage prop that breaks down when he tries to activate it. But the point of Act II George is that he's worried his art is beginning to grow stale, as shown in his conversation with the art critic and the song "Lesson #8."
In the musical In the Heights, the main character Nina is supposed to be the smartest, brightest, and overall "best" in her community. As far as the audience can tell, the only thing she ever accomplished was getting into Stanford, where she promptly lost her scholarship due to poor academic performance.
The elder Dr. Narbon's mad science skills in Narbonic. Another character brings this up eventually.
Dave: She used your death ray, the conspiracy's teleporter... doesn't she invent anything of her own?
Dr. Narbon's clone: She made me.
Dave: ... Okay, she's a one trick pony.
Least I Could Do features Rayne, supposedly a master at picking up chicks. Yet virtually every strip featuring him hitting on a girl shows his asinine pick-up lines, childish behavior, and utter shoot-downs from the girls. 95% of the time, his hook-ups are only shown AFTER they've already happened. Sure, Rayne's supposed to be good-looking, but it's more than a little obvious the writer doesn't really know how a master pick-up artist works.
There's also his job, in which it's repeatedly stated he isn't fired for constantly leaving early or acting offensive because he's a business genius. However, most times he's at work, we get generic lines about meetings or when shown in detail, his decisions are actually quite naive and would be disastrous in the real world, such as giving away free eBooks in the hopes people will use them to subscribe to a digital newspaper.
In Sonichu, Chris has given descriptions to each of the female characters' personalities, ranging from "smart and quick-wit" to "generic high-school girl personality." Of course, we never actually see any of this, since every female character is either interchangeable or useless.
In Homestuck, the Kids share a skill with their Guardian, but not as well: John is always bested in prank wars by Dad, Rose falls short of Mom's insane passive-aggression, and Dave is just not as cool, fast, or ironic as Bro. They still try to build up these abilities as part of their core personalities.
Subverted when the Kids meet; Rose acknowledges that she "cannot hope to defeat [John] in a prank-off. He is simply the best there is." Rose also acknowledges how amazingly cool Dave is when he shows off his audio gear and some of his mixes.
Theoretically, all players are supposed to have an ability that has to do with their legendary title (eg. Dave is the Knight of Time, and thus uses time travel in combat), however, not all characters reflect this: Karkat, Tavros, and Nepeta, for example, being the Blood, Breath, and Heart players respectively, have never been shown to have any overt special powers despite their titles.
Gemel from Tony TH is supposed to be very powerful, but always gets Curb-Stomped whenever he appears. This is actually justified though, for two reasons: A) while Gemel has a lot of power, he really can't take a hit, and B) he always fights alone against groups of good guys. The end result is that the heroes spend the entire battle blindsiding him whenever he tries to make an attack, making it less of a battle and more of a game of tennis with Gemel as the ball. During the few times he fights one-on-one or as part of a group, he actually lives up to his reputation.
In El Goonish Shive, Susan's magical powers, which are seen exactly once and then aren't visible for many arcs. Then Susan explains that Nanase's powers are of a different order than hers ("Awakened" vs. "Dreaming") without going into detail—until much later, when Susan explained her magical abilities with a bigflashback. And she is properly "Awakened."
Tom, a boy from Moperville North high school, is touted by an ex-girlfriend as a highly skilled Manipulative Bastard who has set his sights on Susan. While his initial interaction with Susan bears this out, when she unknowingly throws him a curve ball (telling him she has no interest in dating, period) he fumbles badly and his attempts to regain his footing only tip Susan off to what he's doing.
Ruby of Sticky Dilly Buns has a BBA, giving her apparently far better academic qualifications than the rest of the cast. Admittedly, book-smarts aren't everything when it comes to intelligence, but still, she shows no clear signs of being more intellectual or focused than anyone else.
In Tales of MU, Amaranth seems to border on having Informed Flaws. Word of God is that if the author had wanted to write a Mary Sue, it would have been Amaranth without the flaws. The problem is that while Amaranth's perspective on some matters is clearly skewed, her actual effect on the storyline is always extremely positive. Even her informed flaws are that she's not quite perfect. She's not quite as genius-level smart as she thinks she is, she's not quite perfectly adjusted, and she's not quite as sensitive and empathetic as someone perfect would be. Saying Amaranth has flaws is like saying that an M&M is less chocolatey than a Hershey's Kiss.
In lonelygirl15, the main characters have a strange tendency to panic whenever they see Lucy show up. As a sunglasses-wearing Order operative, there is reason to consider her dangerous by default, but she is treated as if she were the single deadliest person that could be thrown at them. She gets nastily proactive toward the end of the series, but before that point, her greatest known feat was physically restraining a smallish teenage girl.
The behind-the-scenes InsideLG15 videos do include non-canon clips of Lucy shooting Danielbeast in the crotch and shooting P. Monkey in the head.
Adonis Zorba of Survival of the Fittest is played up as a awesome fighter, excelling in multiple fighting disciplines, however in his brief fight with plain-old boxer Bobby Jacks (admittedly a hulking Scary Black Man) Adonis came very close to getting his ass kicked. Notable also is that previously (in a pregame tournament) Bobby was defeated with relative ease by an opponent with far less 'fighting ability' than Adonis is touted to have.
Dan Brent, of V3, is a decent example of this, as his every attempt to score kills fell horribly flat.
Laura, as in legolas by, has apparently "got a power and she can distoy us all the bad guys". She never actually uses this power, even when she's imprisoned and tortured by the orcs, or during the big important final battle, and what the power is supposed to be or do is never actually described.
Played for Laughs with Dr. Tran. The audience is constantly told about how he's a badass secret agent who has a PhD in kicking your ass and once killed his mother with a broken lawn chair. In reality, he's just a very confused Chinese boy who's constantly harassed by the narrator.