In the 'izuku hates all might fanfiction', it could be that Izuku discovers some dark secret about All Might. For example, if All Might has been using him as a pawn in a larger scheme. This realization would shatter Izuku's previous admiration and turn it into hatred.
Perhaps in the fanfiction, All Might is written as being overly critical of Izuku. Constant negative feedback and high - pressure expectations can make Izuku resent him. Also, it could be that All Might is shown as being responsible for some misfortune in Izuku's life, like getting him into a dangerous situation without proper support.
In the fanfiction, Izuku may start to undermine All Might's actions. He could try to expose any flaws or wrongdoings of All Might. Their relationship goes from one of idolization and guidance to one of opposition. Izuku no longer looks up to All Might and may even try to bring him down. For example, he could spread rumors or try to find evidence against All Might if the story goes in that direction.
One possible reason could be a misunderstanding. Maybe Naruto heard some false rumors about All Might's actions in the hero world that made him form a negative opinion. For example, if there were rumors that All Might was too self - centered in his heroics, Naruto, who values teamwork and selfless acts in his own ninja world, might start to dislike him.
Sometimes, the source material itself can be a factor. If there are major changes in the official My Hero Academia storyline related to Izuku, it might make the author's original concept for the fanfiction no longer viable. Or perhaps they had planned the fanfiction to be part of a certain arc in the series, and when that arc didn't play out as they expected in the official story, they abandoned their work.
One reason could be that in some fanfiction, the characterizations of Sasuke and Sakura might be off. Maybe Sasuke is portrayed as overly cruel to Sakura in a way that doesn't seem true to his character in the original series. Another reason could be that the storylines in these fanfictions are too clichéd, like always having Sasuke constantly reject Sakura in the same uninteresting ways.
One possible reason could be that some fans want to explore a different dynamic. In the original story, Edward and Bella are in love, but in this fanfiction, perhaps the writer wants to show a more complex relationship where Edward hates Bella. Maybe it's to add more drama or to explore an alternative storyline that goes against the typical romance.
One reason could be that in this fanfiction's unique plot, there is a prophecy or some ancient magic that has been misinterpreted. This misinterpretation leads Harry to think that Muggle - borns are somehow linked to an impending doom for the wizarding world. So, as a result, he harbors hatred towards them. It could also be that there has been a series of unfortunate events that he wrongly blames on Muggle - borns, like a magical accident that he believes was caused by their 'uncontrolled' magic.
There could also be political reasons. Some factions within Konoha might have seen Naruto as a tool or a threat to their own political power. His influence and popularity could have disrupted the existing power balance, leading to animosity from those who wanted to maintain the status quo.
One possible reason could be a simple rivalry over a shared love interest. Maybe they both like Naruto, and Hinata's jealousy towards Sakura because of Naruto's attention to her could be depicted as hatred in fanfiction.
Well, in 'harry hates hermione fanfiction', it could be that the writer is trying to show how misunderstandings can lead to such extreme emotions. For example, perhaps there was a miscommunication about a spell or a magical event that made Harry wrongly think Hermione had betrayed him. Or it could be a way to explore how different personalities might clash more severely than shown in the original series, like Harry's impulsive nature conflicting more with Hermione's logical thinking.
One possible reason could be that he has had bad experiences with teachers who underestimated him. For example, they might have not recognized his potential and discouraged him from pursuing his dreams, which could lead to his hatred.