"Writing anything - or constructing any kind of story - is, inevitably, more re-writing than actual writing (and the same thing goes for storyboarding, of course). For every step forward there’s always two, three, four or fifty steps backwards. Every element of a story is always in flux as you’re writing: the characters constantly change to fit the story better, or as you get to understand them better, and the same goes for the settings, the events, the dialogue, and every other aspect as well."

Good point, from Mark Kennedy over at Seven Golden Camels