A lot of actors go through that. They've gotta do their movie which puts them in the big leagues. Godfather was that movie for Pacino. I think Pacino's acted in enough roles, to where he's known as Pacino, not as Michael Corleone, not as Tony Montana. The fact that he's chosen to live the Hollywood lifestyle just contributes to his drug/alcohol abuse (it's a common thing). Godfather never "spoiled" Pacino's career, it only enriched it, and got the ball rolling. After directors see what you can do with one role, they'll want to see what you can do with others.