Conversation so far:
How did Lord Voldemort's character begin?
In a 1999 interview, J. K. Rowling said Lord Voldemort was invented as a nemesis for Harry Potter, and she intentionally did not flesh out Voldemort's backstory at first.
Why did J. K. Rowling not flesh out Lord Voldemort's backstory at first?
Harry Potter didn't know he was a wizard so when the most evil wizard tries to curse him and it rebounds, leaving a scar, the evil wizard goes into hiding.

Question: How else is voldemort's character developed?
Self-contained rewrite: How else is Lord Voldemort's character developed?