Why do you write what you write?

Flannery O’Conner once said, “I write to discover what I know.”To discover what I know about people of whom I've only met in my head and tell their story is quite amazing. I write to write their stories. 

On another note, I am unofficially writing with the NaNoWriMo again. Tentative title is Paper Nests. I've had a busy October but I did squeak out a “Beat Sheet”, simple character sheets and a list scenes. It's enough to get me going. 

Are you writing with the NaNo? If you write, why do you write? If you're a reader, what connects you most to a story. The characters? The story line? A specific genre? Something else?