The MCU, for all its greatness, has a bad habit of marginalizing important characters. Sometimes that's done by killing off a character well before they should have. An example is the Red Skull, a character too important to confine to one movie. Thankfully, he did get a fun cameo in Endgame.
Others never had an important role to begin with and were cast off as if they were D-list villains, despite their important positions in the comics. It's not just villains either, there are more than a few heroes who received the same unfortunate treatment. It's a big issue in the Thor films.
10 Arnim Zola Should Have Had A Far Larger Role In Winter Soldier
The use of Arnim Zola in Winter Soldier was a complete and utter waste. It's revealed he helped experiment on the Winter Soldier to ensure the former hero didn't die and that Zola himself managed to survive physical death by uploading his consciousness into a computer. Rather than this being a big reveal, it was a lame exposition scene that explained how HYDRA had infiltrated S.H.I.E.L.D.
He should have been the primary villain of the movie rather than Alexander Pierce. He's too integral to HYDRA to be tossed by the wayside as quickly as he was.
9 Quicksilver Only Lasted One Movie & Never Felt Important
The Maximoff twins felt like also-rans when they teamed up with Ultron, often overshadowed by the android villain. Unlike Wanda, Pietro didn't get much time to develop as a character. All he had going for him was that he was fast, and that was the extent of his character for the majority of Age of Ultron.
His sacrifice at the end of the movie didn't feel like it had the impact it should have because he wasn't around long enough for the audience to care about him. It's difficult to form a connection with a character who swaps sides and then dies in the first movie they appear in.
8 Sharon Carter Disappeared After Civil War & Only Recently Has Started To Gain A Role In The MCU Again
To the MCU's credit, they seem ready to remedy this problem as Sharon Carter played a role in Falcon & Winter Soldier and appears ready for a larger role going forward.
That said, it doesn't excuse the fact she disappeared from the face of the earth after the wrap-up in Winter Soldier and Civil War. What makes it worse is there's no chance to have her and Steve together on the big screen, despite how tied the two are in the comics. She felt wasted in the films as a result.
7 The Mandarin Was A Fake & Is Thankfully Getting Proper Treatment In Shang-Chi
As with Sharon Carter, the MCU is trying to make up for their mistake by bringing The Mandarin back into the universe. The problem is the same as with Carter, the main character their comic counterpart interacts with is no longer present. The Mandarin's story is tied to Iron Man's, and in many ways, he's Tony's arch enemy.
The decision to make him a fake in Iron Man 3 was a colossal misstep by Marvel and was met with disdain from comics fans. The fact Ben Kingsley could have been a good Mandarin makes the bait and switch even worse.
6 Betty Ross Disappeared Along With Edward Norton's Hulk
If there's one character the MCU has yet to fully grasp, it's The Hulk. Edward Norton's film is one of the weaker ones in the universe, and Mark Ruffalo's version of the character is nothing more than an ensemble piece.
Rarely is Ruffalo ever allowed to have character development on screen, and that may be why Betty Ross has all but disappeared. Why have Bruce's primary love interest when there isn't any interest in his character? It's just funny that Thunderbolt Ross came back, but not his daughter.
5 Baron Von Strucker's Entire Purpose Was To Explain Why Scarlet Witch & Quicksilver Weren't Mutants
As with Armin Zola, Von Strucker is an integral part of HYDRA and one of its highest-standing members. After his mid-credit scene during Winter Solider, it seemed like he'd be set up as at least a secondary villain of the next Avengers or Captain America movie, as they put HYDRA to bed for good.
That was the wrong assumption as his appearance in Age of Ultron was barely longer than his introduction. His whole purpose was to explain that the Maximoffs weren't mutants.
4 Miek Is One Of The Many Characters Butchered By Smashing Planet Hulk Into A Thor Story
Thor Ragnarok may have been an entertaining movie, but it butchered the Planet Hulk storyline it tried to adapt into a Thor movie. There were so many characters outright missing or reduced to nonexistent roles.
The worst of these is Miek, who went from an initially meek and scared gladiatorial combatant to master manipulator in the comic story. In the movie? He just exists, so Korg has someone he can talk to.
3 Korg Lost All Of His Depth & Became Comic Relief
Miek wasn't the only Planet Hulk character flattened by the reimagining of Planet Hulk. Korg became a completely different character than he was in the comics. Rather than an honorable warrior who at one point had to fight against his brothers in the gladiator ring, he was a joke-dropping machine that never took anything seriously.
While he was certainly funny, he became a marginal character when he played a large role in Planet Hulk.
2 Lady Sif Got Replaced By Valkyrie & Completely Forgotten About In Thor
The Thor movies botched Lady Sif in so many ways that it's surprising she even showed up in Loki. Despite appearing in two movies, her presence felt nonexistent beyond a few action scenes. That's sad for a character who plays as much a part in Thor's life as Jane Foster does, yet Jane hogged all of the screen time, and Sif did nothing at all.
Sadly, Agents of S.H.I.E.L.D managed to capture her character better than the movies did. To make matters worse, her role as a female warrior has been diminished by Valkyrie, so she has even less importance now.
1 Skurge's Last Stand Against Hela's Army Didn't Have The Same Impact As In The Comics
Skurge's role in Ragnarok felt like a bit of an afterthought for most of it, mostly because the movie felt like it was broken into two separate mini-movies. As such, the sacrifice he made to allow survivors to escape Asgard felt a bit hollow. He didn't have enough time to develop as a character for his death to matter, and it lacked the impact the moment had in comics.
It didn't help that his reasoning for a bad guy was flimsy at best. He would have been better served to be in a movie where he and Amora were the primary villains, and then he made his stand in a follow-up against Hela.