Maverick movie-maker Robert Rodriguez credits his success to a huge fear of failure.

The Sin City director is convinced his work would suffer if he ever lost his inhibitions and stopped worrying about critics' reactions to his films.

He says, "There's a fearlessness that children have which you have to try to keep. Because as you get older, you start fearing too much and that's why drink or drugs will free you up to let the fear go.

"But fear is part of the creative process. Am I good enough? Can I do it again? That's all part of creating.

"No matter how good you get, you should always be afraid. It drives you to be better."