When you produce a film there are many things to consider, arguably most importantly things like budget, schedule and safety. Sure, you should have a good story too, but let’s trust that the writer and director has that one covered. As a producer you want to make sure that your director’s vision can be realized within the budget you have available, without adding extra shooting days or compromising the safety of cast and crew. But you can only identify these possible hazards (financial or physical) if the script is locked.