Sometimes, Dumbledore might try to control Harry by manipulating the information he gives him or influencing his decisions without him realizing it.
Dumbledore could try to control Harry in fanfiction by setting up certain circumstances or tasks that seem beneficial but are actually part of a larger plan to control his path. Maybe he also uses emotional manipulation or plays on Harry's loyalty and sense of duty.
Maybe it's because they think it's for Harry's own good or to protect him from some perceived danger.
Harry might initially be confused. He has always looked up to Dumbledore, so when he realizes Dumbledore is trying to control him, he could start to question everything he thought he knew about their relationship. He may become more rebellious as a result, trying to break free from Dumbledore's influence and make his own decisions.
It could be that Dumbledore has some strategic or protective reasons. Maybe the electives Harry chose initially could expose him to greater risks or prevent him from developing crucial skills needed later on.
Maybe it happened because he made a big mistake in a magical experiment or broke a strict school rule. That might have triggered a howler being sent to him. The possibilities are endless in fanfiction!
It could involve Dumbledore teaching Tom differently and shaping his character in unexpected ways. Maybe it leads to a completely new dynamic between them.
Harry might outsmart Dumbledore by having a deeper understanding of the Horcruxes. If he discovers something new about Horcruxes that Dumbledore missed, perhaps a hidden weakness or a way to detect them more easily. This could give him an upper hand, especially since the Horcruxes were such a crucial part of the battle against Voldemort.
One reason could be that Hermione is overly worried about Harry's safety. Since he's always in the middle of dangerous situations, she might think controlling his actions can keep him out of harm's way.
It could be that Dumbledore is afraid of what Harry might do if left to his own devices. Harry has a lot of power, and Dumbledore may worry that he could be swayed by the wrong people or ideas. So, in an attempt to keep Harry on the 'right path', he resorts to trying to control him. But this also shows a lack of faith in Harry's character and judgment.
Often in fanfiction, Dumbledore helps Harry understand the nature of Voldemort's soul - splitting into Horcruxes. He may guide Harry in the search for these Horcruxes. Dumbledore could also use his own powerful magic to shield Harry from Voldemort's attacks, at least until Harry is fully prepared for the final confrontation.
As mentioned before, a powerful dark wizard could be one of the characters. This dark wizard might see Harry as a threat or a tool to achieve his evil plans and thus tries to control him. He would use all kinds of dark magic and cunning strategies to bend Harry to his will.