You're making a movie, not a documentary. If you made a film like the historians would like you to make, you're not going to go and see it. I'd rather see paint dry.
When you do bigger films, the financiers take more risks.
Sometimes you just can't walk away from films you're offered, like the Dylan Thomas thing.
I try and do films I know I'm going to enjoy watching as well as being in.
The success of the film is down to the crew.