If your talking about making into a movie, It's so people could see it how stephanie saw it. Her view became your view. kusoma the book wewe could imagine many things for Bella but in the movie wewe see the only face for Bella, Edward, Emmett, etc. Also because the vitabu were a hit then why wouldn't the sinema be a hit? People would make a lot of money and those playing the main characters would be known world wide. If your talking about the book it's a simple answer. See Stephanie had a dream which made her sit down and right it. She got engrossed with it and ended up making a whole saga. I mean it can happen. Plus uandishi is a passion to her. Maybe she just wanted to make a new era a Wanyonya damu to.