One possible reason could be that Harry discovers some secrets that Dumbledore has been keeping from him. Maybe Dumbledore has been making decisions about Harry's life without his knowledge, like how he was set up to face Voldemort. This lack of transparency might lead Harry to lose trust in him.
One possible reason could be miscommunication. Maybe Ron said something that Harry misinterpreted, leading to the distrust. For example, if Ron made a joke about Harry's abilities in a time of stress, Harry might take it the wrong way.
It could also be that in the fanfiction, McGonagall has shown some form of bias. Maybe she seems to favor certain students or groups over others, and Harry, being the one who always stands up for fairness, starts to distrust her when he notices this behavior. He might feel that she is not as just as he once thought her to be.
Another reason could be outside influence. If there were dark forces trying to drive a wedge between Harry and the Weasleys, they might plant false ideas in Harry's mind. This could make Harry question the Weasleys' loyalty, even though they are truly his friends.
One possible reason could be that she discovers some of Dumbledore's past actions that seem morally ambiguous. For example, his handling of the situation with Tom Riddle when he was at Hogwarts. Maybe she finds out some details that make her question his judgment.
One possible reason could be that Harry discovers some hidden actions of Dumbledore that seem manipulative. For example, if Dumbledore has been keeping secrets about Harry's past or his destiny without fully explaining them. Harry might feel used or deceived, leading to his distrust.
One possible reason could be that in the original story, many adults failed him. For example, Dumbledore, while having good intentions, often kept Harry in the dark about crucial matters. In fanfiction, this could be amplified. Harry might have seen adults make decisions that put him and his friends in danger without consulting them. Another reason could be that some adults in the wizarding world have their own political or personal agendas that conflict with what Harry believes is right, so he doesn't trust them.
Another reason could be personal insecurities on Harry's part. Harry has been through a lot and might be over - analyzing Ron's behavior. He could be projecting his own fears onto Ron. For example, if Harry is worried about being betrayed again like he was by some people in the past, he might start to doubt Ron even without solid evidence.
It could also be that Harry has his own ideas about how to deal with the situation at hand. He might think that Dumbledore's approach is too cautious or too risky. For instance, if there's a threat from Voldemort, Harry might believe that a more direct and aggressive strategy is needed rather than following Dumbledore's more calculated and long - term plans.
Maybe Harry discovers some things from Dumbledore's past that seem unethical to him. For example, Dumbledore's association with Grindelwald in his youth. Harry, who has a strong sense of right and wrong, might find it hard to trust someone with such a controversial past. And in the fanfiction, the author might explore how these revelations shake Harry's faith in Dumbledore.
It might be due to hidden secrets. If there are dark secrets within Konoha that Naruto discovers in the fanfiction, such as a conspiracy that involves some of the higher - ups. This would make him lose trust in the village as a whole.