Writing, to me, is like kayaking a river. You are paddling down, and you come to a walled-off canyon, and you make a sharp turn, and you don't know what's around the corner. It could be a waterfall, it could be a big pool. The narrative current carries you. You're surprised, and you're thrilled, and sometimes you're terrified.
When I first started writing, it was me alone with a computer in my apartment. I hated the time away from other people, and my writing sucked. Now I have a laptop; I can do the most tedious part of my job in a public place.