I think it would be pretty boring if you knew everything about a character before you wrote their story. Writing, for me, is an act of discovery. The Rashamon</> model is a great way of discovering if you used the right point of view for a story. Has everyone here read The Good Soldier? In the course of the story, you realize the narrator understood anothing about what was going on around him. It is a slender book that has a lot to teach about character development, because your perspective of the characters is completely turned around by the end of the story, and how the author manages to conceal the facts behind his narrator's viewpoint is interesting to observe.