I always figured that once I wrapped a film, then anything beyond that is none of my business. If I can avoid seeing the final product, then all I have in my head is feeling good about the experience.
For me a film is at its best when you can start filling in the story with your own life experience.
A good film is when the price of the dinner, the theatre admission, and the babysitter were worth it.
A good book does not necessarily make a good film.