As I watched Peter Bogdanovich interviewing David Chase on the first season Sopranos DVD, I was a little irked by Bogdanovich constantly referring to his index card questions, but soon I just got into the answers and the explanations. Chase describes how he created the show, first as a pilot for Fox and then as an HBO series. At one point, Bogdanovich mentions something that Orson Welles had told him in response to something that John Ford had told Bogdanovich in another interview: "most of the good things [in filmmaking] happen by accident'. And I repeated this to Welles... I said 'is that true?' And Orson said, 'yes, you could say that the director is a man who presides over accidents'." He also mentions it here.