History TheyWastedAPerfectlyGoodCharacter / MyLittlePonyFriendshipIsMagic

* [[EvilOverlord King Sombra]], out of all the main antagonists -- if not out of every single antagonist in the show, or even any character period -- is the only one who has had no opportunity to experience any character focus, despite being highly competent and frighteningly dangerous. With little interaction with the mane cast, barely any dialogue, very little screen time, he was written as more of a mindless beast than an actual villain. There was evidence to suggest he was going to be the show's first recurring villain, until the [[ComicBook/MyLittlePonyFriendshipIsMagicIDW official comic]] used Queen Chrysalis to fill that position. This was somewhat mitigated with him not only getting the longest BadFuture scenario in the Season 5 Finale, but also being played as one ''hell'' of a scary villain as opposed to the AdvancingWallOfDoom characterization he got in his first appearance. He finally comes back in full form in the Season 9 premiere.

* Celestia, although she appears in numerous episodes, never receives any character focus like Luna and exists mostly to provide exposition. What hints do exist as to her past and personality -- especially the ones that might indicate she's TheWomanWearingTheQueenlyMask -- are tantalizing enough to make her a prime target for fanfiction writers, but they're only hints and near nothing is really known about her. Celestia fans are quite irked that she seldom gets to do ''anything'', that when she does she gets soundly [[CurbStompBattle stomped to the curb]] so the Mane Six can save the day instead, and that she had next to no screentime in the Season 5 Premiere and Finale. In Season 7, Celestia ''finally'' [[Recap/MyLittlePonyFriendshipIsMagicS7E10ARoyalProblem gets her due]], sharing the spotlight with Luna and finally revealing how difficult their respective jobs are, and she '''finally''' gets [[Recap/MyLittlePonyFriendshipIsMagicS8E7HorsePlay an episode to call her own]] in Season 8 when she's championed to act in a play in spite of being a god-awful actress.

* [[TagalongKid Spike the Dragon]] was accused of this in the show's early days. He's shown time and time again to have some quite amazing abilities, from swimming in lava to fire breath that can melt locks or [[SugarWiki/MomentOfAwesome stadium-sized pieces of ice]], HiddenDepths, and a rather mysterious backstory due to no one knowing exactly how Celestia ended up with his egg to begin with. But in the episodes where he even makes an appearance he's either thrust into the background or serves as a source of ComicRelief. Starting with Season 6 he gets more opportunities to shine, notably with "[[Recap/MyLittlePonyFriendshipIsMagicS6E5GauntletOfFire Gauntlet of Fire]]" and "[[Recap/MyLittlePonyFriendshipIsMagicS6E17TheTimesTheyAreAChangeling The Times They Are a Changeling]]", and from that point the writers started treating him less as ComicRelief and more as a main cast member in his own right.

* The Pony of Shadows [[spoiler:(Stygian)]] despite having an amazing design and backstory, is the least recurring antagonist of the entire series, appearing in only two episodes late into the season seven finale. His redemption arc came too fast resolving all conflict. Considering the aforementioned shadowy King Sombra was poorly utilized and underdeveloped as a villain, and a mythical entity referred to be the same name (Pony of Shadows) was implied in season four alluding to the idea the accumulated hatred of Nightmare Moon lived on, claiming another pony as its vessel, fans were disappointed all three were not one and the same character they speculated the series was building up to.

* Sugar Belle, Party Favor, Night Glider, and Double Diamond in Season 5 premier were the only members of Starlight Glimmer's cult with full characterization, interaction with the Mane Six and Starlight, and played an equal if not greater role in saving the day than the heroes, suggesting they would become major characters. But they only had a few minor appearances by the Season 6 finale, never explaining [[DarkAndTroubledPast what they went through]] that would make them want to join Starlight's cult, how/why the former three wished to rebel against it unlike the others and Double Diamond became Starlight's right-hand pony, or why they immediately forgave Starlight despite everything she did which could have addressed criticisms of Starlight's redemption and wasted potential as a villain. Afterwards only Sugar Belle would [[AscendedExtra get a prominent role]] as Big Macintosh's LoveInterest, but still not enough to explore those aspect out, while the rest were limited to cameos.

* The Young Six. They had potential both individually and as "next generation heroes", but unfortunately by the time they were introduced, the show's next season would be its last. Because of this, the final season had to focus on giving send-offs to its more established characters, leaving the Young Six with less character development.

* Cozy Glow, a [[EnfantTerrible pegasus filly]] who commits terrible crimes against all of Equestria both in Season 8 and Season 9, and, in terms of villain effectiveness, even comes on par with ''Lord Tirek, Queen Chrysalis, and King Sombra!'' And yet, we ''never'' get a chance to find out ''[[MysteriousPast what]]'' caused her to become so evil or [[ParentalAbandonment the identity of her parents]], especially considering how alien the concept of a child being so focused on maliciousness and power without a strong explanation is.

* [[TagalongKid Spike the Dragon]] was accused of this in the show's early days. He's shown time and time again to have some quite amazing abilities, from swimming in lava to fire breath that can melt locks or [[SugarWiki/MomentOfAwesome stadium-sized pieces of ice]], HiddenDepths, and a rather mysterious backstory due to no one knowing exactly how Celestia ended up with his egg to begin with. But in the episodes where he even makes an appearance he's either thrust into the background or serves as a source of ComicRelief. Starting with Season 6 he gets more opportunities to shine, notably with "[[Recap/MyLittlePonyFriendshipIsMagicS6E5GauntletOfFire Gauntlet of Fire]]" and "[[Recap/MyLittlePonyFriendshipIsMagicS6E17TheTimesTheyAreAChangeling The Times They Are a Changeling]]", and from that point the writers started treating him less as ComicRelief and more as a main cast member in his own right. Though whether or not they should've explored his origins is still hotly debated, fans on the whole tend to dislike how, [[Recap/MyLittlePonyFriendshipIsMagicS2E21DragonQuest twice]] [[Recap/MyLittlePonyFriendshipIsMagicS8E24FatherKnowsBeast now]], [[BaitAndSwitch they've teased the prospect of diving into his origins without actually doing so]] -- fans either believe they should answer the question they themselves raised, or just not ask it in the first place.

* Many of the one-shot races like the Diamond Dogs, Buffalo, Saddle Arabians and Kirin never got much of a showing after their debut episodes. Relatedly, of the other sentient species of Equestria, very little is known about them and PlanetOfHats is always in full effect when depicting their respective cultures.

* Many of the one-shot races like the Diamond Dogs, Buffalo, Saddle Arabians and Kirin never got much of a showing after their debut episodes.

* All of the other sentient species of Equestria, very little is known about them and PlanetOfHats is always in full effect when depicting their respective cultures.

* Lightning Dust was originally supposed to become Rainbow Dash's wingpony and to remain friends with her but she was publicly humiliated and expelled instead.

* Lightning Dust was originally supposed to become Rainbow Dash's wingpony and to remain friends with her but she was publicly humiliated and expelled instead. They were an amazing team and could learn much from each other but it took until Season 8 for this to be averted: she returns as the leader of a rival team known as The Washouts and, albeit haven [[TookALevelInJerkAss taking a level or two in jerkass]], managed a surprisingly amicable relationship with Rainbow Dash and firmly established herself as TheRival.

* [[TagalongKid Spike the Dragon]] was accused of this in the show's early days. He's shown time and time again to have some quite amazing abilities, from swimming in lava to fire breath that can melt locks or [[SugarWiki/MomentOfAwesome stadium-sized pieces of ice]], HiddenDepths, and a rather mysterious backstory due to no one knowing exactly how Celestia ended up with his egg to begin with. But in the episodes where he even makes an appearance he's either thrust into the background or serves as a source of ComicRelief. Starting with Season 6 he gets more opportunities to shine, notably with "[[Recap/MyLittlePonyFriendshipIsMagicS6E5GauntletOfFire Gauntlet of Fire]]" and "[[Recap/MyLittlePonyFriendshipIsMagicS6E17TheTimesTheyAreAChangeling The Times They Are a Changeling]]", and from that point the writers stopped treating him as ComicRelief and more as a main cast member in his own right. Though whether or not they should've explored his origins is still hotly debated, fans on the whole tend to dislike how, [[Recap/MyLittlePonyFriendshipIsMagicS2E21DragonQuest twice]] [[Recap/MyLittlePonyFriendshipIsMagicS8E24FatherKnowsBeast now]], [[BaitAndSwitch they've teased the prospect of diving into his origins without actually doing so]] -- fans either believe they should answer the question they themselves raised, or just not ask it in the first place.

* [[EvilCounterpart The Mean Six]]. Introduced in the eponymous episode, and had the potential to be an interesting QuirkyMinibossSquad, with Mean Twilight being smart enough to become a major threat. Instead, they're [[KilledOffForReal destroyed outright]] in their debut episode, and the Mane Six never even realize they ''existed''. It's especially bad as Queen Chrysalis continued to hang onto the hunk of wood that was left behind when Mean Twilight was killed well into Season 9, which taunted audiences with the possibility that she might make a return that never happened.

* [[TagalongKid Spike the Dragon]] was accused of this in the show's early days. He's shown time and time again to have some quite amazing abilities, from swimming in lava to fire breath that can melt locks or [[SugarWiki/MomentOfAwesome stadium-sized pieces of ice]], HiddenDepths, and a rather mysterious backstory due to no one knowing exactly how Celestia ended up with his egg to begin with. But in the episodes where he even makes an appearance he's either thrust into the background or serves as a source of ComicRelief. Starting with Season 6 he gets more opportunities to shine, notably with "[[Recap/MyLittlePonyFriendshipIsMagicS6E5GauntletOfFire Gauntlet of Fire]]" and "[[Recap/MyLittlePonyFriendshipIsMagicS6E17TheTimesTheyAreAChangeling The Times They Are a Changeling]]", and from that point the writers stopped treating him as ComicRelief and more as a main cast member in his own right. Though whether or not they should've explored his origins is still hotly debated.

* The family members of the Mane Six are usually subject to ADayInTheLimeLight but these particular examples aren't so fortunate.

* Prince Blueblood is Celestia's nephew about 52 times removed on her mother's side. Outside of being a PrinceCharmless to Rarity in the Season 1 finale, we know next to nothing about him despite being literally a Prince. He was shown in a cameo in "Sweet and Elite" next to Rarity and that's it. With Princess Cadance away in the Crystal Empire, he could have acted as a teacher of royal court life for Twilight in the later seasons. However, outside of a [[Recap/MyLittlePonyFriendsForeverIssue26 comic book issue]], he practically disappeared from the show.

* The [[MinorMajorCharacter EEA]]. They are revealed to the department responsible for the education of Equestria. However, with no episodes showing their side of the argument and how they run the due process, practically all of them came off as StrawmanPolitical who can be opposed without any consequence that it makes you wonder how Equestria hasn't underwent a "brain drain" from all this incompetency. Being never mentioned again after Season 8 really didn't help matters.

* Zecora. Originally planned to be Twilight's second mentor, her entire significance to the overall narrative practically fell off a cliff as that role wound up being scrapped practically entirely save for one episode. Over the seasons, she was reduced to a MacGuffin dispenser whose significance is defined by what potion she cooked up to serve the episode's plot. Outside of that, we practically know nothing else about her to the extent that not even WordOfGod can confirm that Zebras as a race even exist in Equestria.

* The [[MinorMajorCharacter EEA]]. They are revealed to the department responsible for the education of Equestria. However, with no episodes showing their side of the argument and how they run the due process, practically all of them came of as StrawmanPolitical who can be opposed without any consequence that it makes you wonder how Equestria hasn't underwent a "brain drain" from all this incompetency. Being never mentioned again after Season 8 really didn't help matters.

* Spitfire and the rest of the Wonderbolts are criminally underutilized in the series. Spitfire appeared at least OnceASeason, but most of her roles were limited to maybe one scene an episode with maybe one or two lines of dialogue at most. Even after Rainbow Dash joined the team, next to no time was shown of her working with them for much of the show, with their appearances still being limited all the way to the end of the series, something that could have used more of to show them working with Rainbow and getting some more characterization.