The only thing you need to make a film is to not be afraid of anybody or anything. John Cassavetes said that. John was inspiring, but he was also direct. He knew that there was no time to be indecisive, or to worry about whether the decisions you’ve already made were right or wrong, good or bad. I think that for John, there was no such thing as a “mistake”—you can only move forward, you can never move backward, and you can profit from absolutely everything.
Martin Scorcese, Tell Me Something: Advice from Documentary Filmmakers