That way you can play one off the others as you make them compete for the film. If you pass, you may not be able to get a better deal later. Indeed, it is possible you may not receive any subsequent offers. On the other hand, if you accept the offer, you may be foreclosing the possibility of a more lucrative deal down the road. Consequently, it is important to orchestrate the release of your film to potential distributors to maximize your leverage.
Executives often ask to see a rough cut.
They will befriend filmmakers and be quite enthusiastic about the possibility of their company acquiring the film. We are professionals, we can extrapolate and envision what the film will look like with sound and titles. Don't believe them. Most people can't extrapolate. They will view your unfinished film and think it amateurish.