It might be due to a newfound confidence. If Harry overcomes some personal challenges in the fanfiction, like dealing with his fear of Snape, this new - found confidence could spill over into his academic life and make him more focused in class, leading to better grades.
One reason could be that he has a change in motivation. Maybe he realizes that good grades can help him achieve his long - term goals, like becoming an Auror. So he starts to put in more effort into his studies.
One common reason is his determination. Harry has always been a fighter, and in fanfiction, he could transfer that tenacity to his studies. He simply refuses to be bad at academics and works hard to prove himself.
It could be for a specific goal, like getting into an advanced magic course. In the fanfiction world, there might be a limited - enrollment class that requires high grades. Harry, being ambitious, would strive to improve his grades to qualify for it.
One possible reason could be that Harry has some secret study techniques he hasn't shared. Maybe he has a better understanding of practical magic which is more emphasized in the grading system in this fanfic.
One possible reason could be that he is wrongly accused of using dark magic. In some fanfictions, the Ministry of Magic might be more corrupt or easily influenced, and they could frame Harry for something he didn't do, leading to his expulsion.
Another possibility is that the fanfiction writer wants to explore a different side of their relationships. By having Hermione and Ron hurt Harry, it shows the complexity of human (or in this case, wizard) emotions. It could be a way to show that even the strongest friendships can have cracks and that mistakes can be made. It also allows for character development as Harry has to deal with this new situation, and Hermione and Ron may later realize their mistakes and try to make amends.
Perhaps the author is trying to be different. Since so many fanfics already focus on Harry and Quidditch, they choose not to.
One reason could be revenge. Maybe someone he wronged in the past, like a fallen angel or a demon he betrayed, decides to take their vengeance by stabbing him. It adds a layer of drama to the story.
One possible reason could be that he breaks some important rules within the fan - created world. For example, if the fanfiction has a strict code of honor and Naruto is made to cheat in a crucial competition, that could lead to his disqualification. Another reason might be that he is framed by an antagonist. The antagonist could plant false evidence against Naruto, making it seem like he has violated the rules, thus getting him disqualified.
One possible reason could be that she's different. In many fictional worlds, being unique can make a character a target. Maybe her appearance or her abilities set her apart in a way that makes others jealous or feel threatened.
One reason could be false accusations. Maybe someone frames Jaune for a serious offense he didn't commit, like cheating in an important exam or stealing valuable items from the school. Another reason might be his inability to keep up with the academic or combat requirements. If he fails too many classes or consistently underperforms in combat training, the school might decide to expel him.