Originally Posted by Iceman
Box office is more a function of how good a film is expected to be
If that were true then they wouldn't have failures like john Carter or Green Lantern.
Yes the advertising and distribution goes into films that are expected to be good but that is based on them having the film before it's released just like the budget for a film is often decided by how good the script is and who's interested in making it (directors and actors) both of which they know before production begins.
People with a lot of experience know when a film has a small market and when it will have mass appeal and they market it accordingly. The box office is a function of them being right more often then they're wrong.