Characters are vessels of stories. They each have their backstory. I like discovering a familiar character, it is like hanging out with an old friend. I enjoy tagging along on their story arc, discovering along with them. Meeting the mentor, for instance.
Even my husband, who is an agnostic non-reader, digs the foreign wizard archetype. He thinks its hysterical when the [American] Indian or Asian mentor speaks mythic-ly: as it’s often poetic, with mixed metaphors and English as a second language. And it translates as basically:
“It’s like this, you big dummy!”
And just like that, the mentor figure provides humility and enlightenment.
A character in a story may provoke you. You may have strong reactions to their thoughts and actions. Imagine they are speaking directly to you. How are you similar? How are you different? What have you learned?