One of Hank Pym's biggest problems has always been that no matter how good he is in any given area, at least one of his fellow heroes is always better. When he was Giant-Man, he lacked the raw power of Thor or the Hulk, and as a scientist, he's not as well respected as Iron Man or the above-mentioned Mister Fantastic. A Retcon in Mighty Avengers established that many of his neuroses began after he discovered that Iron Man was actually the genius billionaire Tony Stark, which immediately caused Hank to feel inferior.
Cable: I'm not saying you're not a genius, Hank...you were just unlucky enough to be a genius in a time of gods.
In many ways, Reed Richards (Mr. Fantastic) is better than his arch-nemesis Doctor Doom, with regards to science at least; one of Doom's key driving motivations is to prove himself superior to Richards, who has always demonstrated that he's just that little bit smarter and better than Doom. In this case, the rivalry is far from unnoticed, although it's always Doom who actively plans and attempts to humiliate and subdue Reed, who is less interested in proving himself superior to Doom and in fact considers it a waste that Doom expends his still-impressive intellect on what amounts to little more than petty jealousy. It is worth noting, however, that Doom is an equally-powerful sorcerer, and is in fact more powerful than Richards in this respect. However, he still meets the basic nature of the trope, as he is obsessed with besting Richards entirely on his own terms, i.e. with science, and when he uses his formidable skills in sorcery against Richards, Richards nevertheless manages to find some way to outwit him and win. In Secret Wars (2015), Reed finally gets Doom to admit that Reed can do something better than him — saving the multiverse. This convinces the Molecule Man to take away Doom's powers and give them to Reed so he can do just that.
Doctor Strange: Doctor Strange is this to Doom in magic, proving that Doom just can't win. You think he'd be happy being second in two fields to the world's best, but no. It has been stated in "Unthinkable" that if Doom had chosen sorcery over science, he would be Doctor Strange's superior. Strange also had the advantage of being tutored by the world's Sorcerer Supreme, while Doom had only a monastery of mystic monks to teach him.
Reed is this to The Wizard, who has actually given up on beating him with science and just wants him dead so he can be the best, resulting in a whole lot of Frightful Fours, one of which had five members. Reed is surprisingly calm about this, except when it's actually happening; he never sits around worrying about what the Wizard's going to do next.
The Mad Thinker is similarly jealous of Reed's accomplishments, but when Reed actually called on the Thinker to check his math during Civil War (2006), the Thinker was bowled over by what Reed had accomplished and finally conceded that Reed was simply smarter than he was; but then he needled Reed that for all his intellectual accomplishments, Reed lacked the common sense to see that his chosen course in the Civil War would cost him everything he loved.
Dr. Strange is this to Baron Mordo (the other former disciple of the Ancient One) rather than Doom; Doom certainly obsesses less about Strange in particular than the not-so-good Baron does.
While Richards lends his name to the Reed Richards Is Useless trope for a good reason, Doom actually uses his incredible intellect to make Latveria, the nation he rules, into a high-technology utopia. However, Reed's technology is still usually superior to Doom's efforts. Doom also gets away with actively using his technological prowess on Latveria because it's a fictional, highly isolationist country and so not subject to the general Status Quo Is God effect that applies to the more "realistic" areas of the Marvel Universe.
Ironically, in Ultimate Marvel, Reed Richards gets to experience it himself, claiming that he feels inferior to his universe's incarnation of Tony Stark.
The Incredible Hulk: Bruce Banner has been shown to resent Tony Stark because of how beloved and successful Tony's inventions have made him, while Bruce's invention turned him into an out of control freak.
Meanwhile the Hulk serves as this to Ben Grimm, the ever lovin blue eyed Thing. Ben is an accomplished fighter and one of the physically strongest heroes on Earth but the Hulk is just plain stronger and tougher than Ben ever is at his best. The Thing can put up a good fight through a Weak, but Skilled approach that takes advantage of his skill as a fighter rather than his power but most of their battles are usually in Hulk's favor by the end and any clear cut victories on Ben's end come from drastically different circumstances than they normally work under, such as one instance when Ben had received a significant power boost and the Hulk was locked into his weaker Grey Hulk form.
Bruce Banner himself is the "someone better" when it comes to knowledge of radiation and Gamma Radiation in particular. Even Dr. Doom whose Fatal Flaw is an unwillingness to accept Reed Richards is better than him admits to Banner's greater knowledge in that area.
Quicksilver has an interesting case in that it is someone who he very rarely meets, in stories that for the most part weren't canon even when they were written: The Flash. Whenever DC and Marvel has crossovers were both feature, the Flash is much, much faster, and thanks to the Speed Force, have a lot more tricks up his sleeve, which Quicksilver understandably tends to feel inadequate in the face of. Quicksilver does have one advantage, though — hisSuper-Speed comes purely from himself, so it works perfectly fine in both universes, while the Flash gets slowed down or even outright depowered when over in the Marvel universe since there's no Speed Force over there.
A quote from She-Hulk, where the titular heroine fills this role for Titania and is the subject of her husband the Absorbing Man's lecture. She just can't beat her and it just drives her insane. Titania also has this with Spider-Man. When she first appeared, she beat just about everyone she went up against... until she encountered Spider-Man. Her confidence and arrogance evaporated quickly because her strength was useless against Spider-Man's speed and agility. He ran rings around her while effortlessly beating her into the ground. To add insult to injury, afterwards her villainous comrades were not the least bit surprised that Spider-Man kicked her ass...
The Human Torch played this role in early stories. No one character plays the role now. Torch and Spidey eventually switched the roles for awhile. Peter was smart enough that he could keep up with Reed's scientific lectures, developed a friendly rapport with Sue and Ben, and was even good with watching Franklin. There was a period where Johnny resented the fact that Peter was practically more of a member of his own family than he was. They eventually worked this out, though, and became best buddies, until One More Day caused an identity reset. While they're friends again, sort of, now that Peter's again revealed his identity to the Four, they aren't near as close as they once were.
The symbiotes appear to have this as a biological rule, as each symbiote inherits the powers of it's parent to a greater degree. Venom is outclassed by his spawn, Carnage, who in turn is outclassed by his spawn, Toxin. This element was downplayed and eventually phased out completely as the comics continue, however: While Toxin was Put on a Bus, Venom acquired several Superhuman hosts and mutations, while Carnage repeatedly tampered with Multiversal (well, microversal...) energy and Chtonic magic to power himself. Nowadays, whenever the Symbiotes brawl there never seems to be a "definitive" stronger one.
Like Wolverine below, Taskmaster is supposed to be this for the Marvel Universe mercenaries. Like Richard Dragon of DC, he's the one who "trains the best." DC stops Dragon from suffering from The Worf Effect or Badass Decay by not having him around when he's not teaching. Taskmaster gets his butt kicked all over.
Taskmaster actually told Deadpool that Deadpool is really the best mercenary and possibly the best fighter on Earth. It's just that Deadpool's messed-up in the head, making him so crazy that no-one will hire him.
Taskmaster: Truth is, you're that good. You've always been that good. Which won't even get you a cup of coffee until you can figure out how to be a professional...
Played with. The Liberators were certainly trying for this. The Abomination was the Hulk with brains. Swarm summons armies of wasps. Crimson Dynamo has a bigger suit no doubt intended to be higher powered. etc. But the Ultimates counter by revealing upgrades or levels taken in badass. And in the case of the Abomination, being an intellectual isn't very useful when your best assets are your rage and your fists.
"Well, let's see how many super soldiers you create wich don't involve getting big, getting small or telling ants what to do through a helmet, jackass! Bruce Banner was twice the geneman you'll always be and you know it, mister!"
Ultimate X Men: The big problem of Sabertooth. Wolverine has his same powers, and will always be the better one. Even Wraith says so, even when Wolverine escaped and left him with that big facial scar, and Sabertooth volunteers to work in Weapon X.
Wolverine has often claimed to be the best there is at what he does. Perhaps no enemy of his has presented more conclusive evidence against this than Tomi Shido - the Gorgon. Faster, stronger, smarter, more agile, more silent, more skillful, all despite his mutant powers having nothing to do with any of these things. Many of Wolvie's enemies are in some way an equal match for him, but the Gorgon is, simply put, too much for Wolverine, even according to the man himself. It took using his own Taken for Granite powers against him to put him away... but sometimes you just can't keep a bad man down.
See also Mr. X, thought by many to be the most perfect killing machine the world has ever known. After the Gorgon, nobody's taken Wolvie to school quite like he has. And before you dismiss his Combat Clairvoyance as cheap, it's hard to argue with a guy who can kill you with both hands behind his back.
However, Quicksilver is this to Mr. X, as while his limited clairvoyance may give him the edge against normal or enhanced humans, it doesn't mean shit when you're going up against someone who can hit you a thousand times before you've even managed to clench your fists. It's notable that Mr. X always makes every effort to stay in or close to his weight class when picking opponents, as anyone with more than Wolverine's power level is simply out of his league.
Wolverine and Spider-Man have fought a couple of times, and every single time, Spider-Man has basically handed Wolverine his ass. Of course, this could always be chalked up to Wolverine simply not fighting in the same weight-class as Spider-Man. (Spidey is outright superhuman and while Logan has on rare occasions demonstrated greater than human physical power he's generally more dangerous for the adamantium bonded to his bones making him both deadlier and even more difficult to kill than his Healing Factor already does.)
While other writers would abandon the idea, Chris Claremont has stated that he intended Sabretooth to be Logan's someone better. Creed would regularly track him down on his birthday, every year, ambush him, and defeat him every single time (Logan would have been dead, if it wasn't for his Healing Factor). Claremont explained their relationship in an interview as;
Claremont: Father and son. That's why Sabretooth always considered Logan "sloppy seconds" to his "original" / "real deal." The other critical element in my presentation of their relationship was that, in their whole life, Logan has never defeated Sabretooth in a knock-down, drag-out, kill-or-be-killed berserker fight. By the same token, on every one of his birthdays, Sabretooth has always managed to find him, no matter where Logan was or what he was doing, and come within an inch of killing him. For no other reason than to remind him that he could.
This is weirdly inconsistent with Wolverine (James "Logan" Howlett) and Sabretooth (Victor Creed). Sometimes, it's made clear that Wolverine will always be better than Sabretooth and that's why Creed hates Logan. Other times, Creed us better than Logan and this is why he's such a big threat despite his really low ambitions. It's wildly inconsistent and depends on what story you're reading, but is inexplicably constantly brought up. For what it's worth, it was retconned years down the line that Sabretooth was Charles Xavier's first choice for the X-Men, but after finding out he wasn't willing to change his ways, he reneged on that.
Uncanny X-Men (2018) reveals that David Haller a.k.a. Legion has one in the form of Nate Grey a.k.a. X-Man. While Legion is immensely powerful, having vast Psychic Powers that surpass his father's and a Reality Warper to boot, with countless different power-sets, Nate also has vast Psychic Powers and is an immensely powerful Reality Warper. Not only that, but he's more mentally stable (well, Crazy Sane, anyway), much more skilled with his powers, and a much better strategist. Compounding this, Legion was directly responsible for Nate's existence, having caused the entire Age of Apocalypse timeline. Legion is aware of all of this, and is consequently terrified of Nate when he goes off the deep end, but also feels that he is his responsibility. Unfortunately, their one fight is a brutalCurbstomp Battle the length of Nate's cold Breaking Speech after Legion's Lotus-Eater Machine trick pushed every Berserk Button and Trauma Button he had, leading to his bodyjacking the other mutant.
This happens with poor Happy Hogan across the board, albeit always Played for Laughs. He's a capable boxer in his own right and can handle himself in a normal fight, but he lives in a world where Every Other Person Is Super effectively making him the Yamcha of the MCU. When he fights he always either finds himself going up against people like the Badass Normal Black Widow who dumps him on his ass effortlessly or the Extremis-charged Eric Savin who No Sells his attacks, and when he does take down a normal opponent like one of Hammer's security guards Black Widow takes down about 12 of them in that same time frame. By god he's trying though!
Iron Man 2: Tony Stark for Justin Hammer, who just barely hides his resentment about always being second-best compared to Stark behind his faux grin. In fact, he's not even second-best, he's shown to be a bumbling incompetent fool who's no where close to Tony's league but his massive ego has him convinced that he's only just coming up second-best.
Captain America: Civil War certainly has a few cases of this. Firstly Bucky Barnes is portrayed as an unstoppable killing machine, yet T'Challa defeats him three times. Then he himself is defeated by Captain America, providing another example.
Tony Stark is an absolutely brilliant engineer and well ahead of his time, but as Rocket sourly reminds him "You're only a genius on Earth, pal".
Live-Action TV
Marvel Cinematic Universe
Agents of S.H.I.E.L.D.: J.T. Jones experiences this when he goes up against Robbie Reyes. Jones is an Inhuman codenamed "Hellfire" (he made it up himself) who can superheat anything he touches. Robbie is the Ghost Rider, a supernatural being who can imbue anything he touches with actual Hellfire, besides being superhumanly strong and tough. The only thing Jones accomplishes is involuntarily loaning his chain to Robbie.
She-Hulk: Attorney at Law: Bruce Banner prepares an outline to teach Jennifer Walters how to be a Hulk, which was meant to take the same fifteen years it took him to get a handle on his powers. He then learns in sequence that Jen; has a Healing Factor he doesn't, doesn't have to deal with a Split Personality at all, already has incredible balance and control over her strength, and can switch to and from Hulk form pretty much at will. He begrudgingly lets her go back to her life as a lawyer in just a few months.
