I agree with Jorge O, they are both important. That said, don't we expose film with a specific development in mind? While, personally I am not at the point to understand N, N+, N- development - I think I understand the reasoning behind it. If the film is not exposed correctly, the final print may not look the way we want - no matter what we do during development. On the other hand if we envision a certain look, expose the film correctly but then apply development other than what is needed the final negative will still fail to yield what we wanted.

Now if I could just get the point where I understand all of this.....