Mikasa Ackerman is the only figure in the Attack on Titan anime universe who'd risk their own life to challenge her abilities. Eren is her Achilles' heel, but she is an amazing fighter who knows that she has to push her limits in order to survive in this terrible world.
Although she may seem like an all-powerful figure, she has her flaws. She is not always in control, and ends up making errors and exhibiting vulnerability. She is relatable in that she is not perfect. However, that also leads to her downfall in many occasions.
Disclaimer: This piece reflects the personal views of the author.
Mikasa Ackerman's commitment to Eren's safety becomes primary reason for her downfall in Attack on Titan among others
1) She is heavily biased towards Eren
Mikasa's character is defined by her unwavering loyalty to Eren. That she wants to protect him from the dangers of the world is commendable, but she is willing to do so at the cost of sacrificing her own well-being.
Eren's physical safety is the only thing that matters to her, which means that she never really develops a personality outside of it. She's still a work in progress. She is enamored with Eren because she believes that he is the sole surviving member of her family. Her response to Eren's reappearance after he was presumed dead in Trost strongly indicates that she wants to hold on to him no matter what.
2) Failure to rein in Bertholdt and Reiner
After discovering that Reiner, Annie, and Bertholdt had been together from the beginning, the Survey Corps chose to keep this knowledge under cover until they could carry out a solid plan. Instead of waiting for Eren to respond, Reiner begged him over and over again for his cooperation. Mikasa was unable to murder Reiner and Berthold once they revealed their true identities, so he was forced to retreat. Her failed attempts increased her frustration.
3) Committing crimes alongside Eren in Liberio
Mikasa may be able to atone for her actions in Attack on Titan, but it's hard to forget her complicity in Eren's plot to destroy Liberio. Her unconditional loyalty cannot be used as a justification for her violent war-provoking actions.
Fans were unanimous in their belief that Eren was the only one who started the Liberio invasion. Despite dedicating her life to protecting Eren, Mikasa could not foresee his behavior and prevent him from committing war crimes before getting involved herself.
4) Her distant demeanor and stoicism
Mikasa's calm demeanor is wonderful and balanced for a person who has been through so much, yet it makes her a protagonist who is difficult to like. Having said that, Mikasa is often misunderstood. She's not a stoic savage in the traditional sense, but a strikingly raw character. We've watched her rise to power, and fall to pieces. She keeps her feelings bottled up and only expresses them to those she loves. As a result, she was initially in desperate need of character growth.
5) Failure to see how much Jean adored her
Jean's infatuation only grows with time. Jean was more open about his sentiments in the beginning than he is now. His true emotions are still betrayed by his actions and nonverbal cues. He's constantly there to protect Mikasa and call her out when she's misbehaving.
She, on the other hand, shows no interest in Jean from the beginning. Like everything else, her lack of empathy for his feelings stems from her fixation on Eren and Armin's well-being.
6) Her ridiculous rage
Eren was a target for the Female Titan, who made many attempts to kidnap the show's lead character during the first season. Mikasa, of course, wasn't happy about this, and she did all she could to halt the Titan in her tracks and bring her down to nothing.
This almost led to her losing her life as she pursued the the Female Titan. Most anime protagonists pursue truth and justice, which prompts them into action. However, in Attack on Titan, Mikasa's anger management issues and her steadfast commitment to her friends lead her down the path of violence.
7) Disregard for Levi's orders
Enraged, Eren seeks to save his friend Armin from death after killing the armored titan. Levi first plans to use the elixir to rescue Armin but, after learning that Erwin is in the same situation, he decides to use it alternatively. As Eren is thrown off guard, Mikasa pins Levi to the ceiling and presses her sword to his neck . Even though she was talked out of making a mistake from which she would never be able to recover, this incident further proves her inability to regulate her emotions. She was imprisoned following this event.
8) Embracing hopelessness
Mikasa struggled to maintain her composure in the face of the Titans after learning of Eren's demise from Armin. She openly mourned Eren's death and coped with her grief in her own manner, revealing that it was all just a front. She was so impulsive in her quest to slay the Titans that, without noticing, she used up all the juice in her gear before embracing death. Fortunately, Eren's transformation saved the day and restored her faith.
9) Not speaking up even when she has something important to say
Although she can fight almost anyone in the world, she almost always backs down when it comes to giving a presentation of her wits. Every time Armin, Erwin, or anybody else expresses their opinion, Mikasa submits to them immediately without offering her own opinion.
On the battlefield, Mikasa's quick thinking is an indication of her brilliance. Yet, she is unable to stop her closest companion from terrorizing whole communities of unarmed civilians. Even though Eren had a bad rep for not listening to anyone, she should have voiced her support for Armin.
10) Her satellite personality
According to certain fans, she is an orbiting or satellite character. A satellite personality is a television cliché that displays a character’s complete core, including motives and temperament, and is centered on their relationship with another character. As a result, the satellite character seems drab without the other person.
As a secondary character, Mikasa's goals and personality center upon Eren Yeager, the protagonist of the story. Some people find her persona to be boring without Eren in the picture.