One reason could be that the fanfiction might have misrepresented Naruto's character. He's a complex character with strong values, and if the fanfiction twisted those, he'd have enough. For example, if it made him out to be too subservient to Konoha when he's always fought for change within the village.
Maybe the fanfiction was too repetitive in its portrayal of Naruto's relationship with Konoha. He has a deep bond with the village, but if every story just kept hammering on the same old themes of loyalty in a dull way, he'd get tired of it. It's like hearing the same song over and over again.
It could be that the fanfiction often puts Kakashi in situations that Naruto doesn't think are appropriate. For example, if the fanfiction makes Kakashi act out of character in terms of his loyalty or his ninja values. Naruto, who has a deep bond with Kakashi, might not like seeing his mentor misrepresented in such ways.
Well, one reason could be that Sakura is often written as being too pushy towards Naruto in fanfiction. He might get tired of her always trying to boss him around or control his actions.
One possible reason could be that Naruto discovers some dark secrets about the village leadership that go against his values. For example, if he finds out that they have been using underhanded means to maintain power.
Maybe Naruto decides to leave Konoha for a while in the fanfiction. He might feel that the village has let him down in some ways and needs to find himself outside of it.
In fanfiction, Naruto might snap at Konoha if he feels betrayed by his friends or the village. For example, if they don't support him when he tries to make important changes or if they side with someone who has wronged him. Also, if the village starts to become too controlling or authoritarian in the fan - created story, Naruto, with his free - spirited nature, would likely snap.
Maybe Naruto has seen too many unrealistic or out - of - character portrayals of Konoha in the fanfiction. For example, some might make Konoha overly cruel or its people too stupid, which goes against his understanding and love for his village.
One possible reason could be to search for a powerful artifact. In many fanfictions, there are often hidden and powerful items that can change the fate of a village or even the whole ninja world. Naruto and Tsunade might leave Konoha to find such an item before their enemies do. This would be a dangerous mission, so they keep it a secret from the rest of the village to avoid panic.
One possible reason could be that Naruto is extremely powerful and his skills are needed to protect Konoha from a new and powerful threat. His combat abilities, like his Rasengan and Sage Mode, are crucial for the village's defense.
Naruto might forgive Konoha because he realizes that holding a grudge won't solve anything. He has seen the destruction that hatred can cause, like during the Pain arc. So, he chooses to forgive in order to move forward and bring about positive change. Another reason could be his respect for the previous Hokages and their ideals for Konoha.
Perhaps she discovers some dark secrets about Konoha's past. Things like the way the village treated certain clans or individuals unfairly. If she uncovers that Konoha was involved in some unethical actions in the past, it could make her lose faith in and start to hate the village. Also, if her loved ones were wrongly treated or sacrificed by Konoha's decisions, that would be a strong reason.