Is it simply impatience trumping common sense? Is it a belief that the writer has such innate talent and genius that he or she can just make up a brilliant script as that draft is written? Or that the backstory is so closely based on the writer's own life experience that there's no need to spend any time upfront exploring it? Or that these kind of "discoveries"--including what the story is ultimately communicating to the audience--are best left to be surprises that pop out of the writing of that draft? Or that if thorough pre-writing work is undertaken the sense of adventure of actually writing pages of script somehow vanishes or is reduced to drudgery?
What I do know is that when writers are introduced to a method of thoroughly exploring a story's backstory before plunging into draft, a whole new world opens up for them in terms of their own creative process. Suddenly characters become more alive and begin to breathe. Subtext takes on a power the writer hasn't experienced before. The story being developed opens up and the characters themselves begin to dictate action and behavior to a much greater degree, and as a result true and genuine surprises present themselves. The writing of the draft becomes much more an experience of writing from the inside out instead of from the outside in.
Because stage and screen stories are about people taking journeys from one place to another and the changes that those people undergo in the process and the discoveries they make about themselves and their world, it only stands to reason that the writers of these stories need to know who their characters are in the most thorough possible way as they walk up to the starting line of the tale they are about to enter. It's the only sure way that the writer can hope to produce a script that has power and any real legs.
There are a number of useful exercises out there that lead the writer into this pre-writing discovery phase. Several are laid out in my book The Playwright's Process, where the emphasis is on character exploration, both in terms of straight forward and detailed biography and deeper, emotionally rich backstory events in a character's life that have shaped who they are up to the start of the story the script is going to embrace. I suggest you try some of these explorations or others with the same focus if you haven't already. I have little doubt that your writing process will be greatly enriched, taking on a new sense of adventure, and that your work takes on a new power and depth.
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