system
Given the following post, respond as if you're commenting on Reddit:
human
[Batman] Why did Dick Greyson leave to become Nightwing?

Is there a definitive version?  Thought I read that he tried to take on Two Face without Batman and almost got killed and Bruce fired him.
gpt
When Robin was 17, he was shot in the shoulder by the Joker, and this scared Batman into ending his career for good. Dick realized at that point that he had grown up: he no longer relied on Batman and, in fact, he and the Dark Knight disagreed on crime-fighting methodology. His new-found independence and Titans' duties in New York left less time for his former commitments in Gotham City. He also dropped out of Hudson after only one semester. Batman, however, was less than pleased. He informed Dick that if he no longer wanted to be his partner, then Dick would have to retire as Robin.