Misguided

Misguided heroes are heroes who inadvertently do the wrong thing mostly because they don't know any better in that particular circumstance. This mainly arises in fables where some wide-eyed youth is set to be taught a lesson over the course of the story, such as The Boy Who Cried Wolf. This may also be done for fully grown competent characters who simply don't see a certain scope of the world they should be concerned with, such as Reeves from Final Fantasy VII or Seto Kaiba from Yu-Gi-Oh!. These characters may still take a staring role in the their works, but the works themselves exist under the notion that said characters start off not knowing any better. Other times, they may be misguided/manipulated by an outside source, rather than themselves alone, and some of these cases may qualify as pawns of the villain, depending on the story or context.

They are also the heroic counterparts of delusional villains.

Misguided heroes can also be purely good since they may have never wanted to cause despair or do the wrong things in the first place while having no corrupting qualities whatsoever.