I will never become a director or a movie producer. I was always looking at picture directing because I didn't know what to do! You can't be a movie director without real preparation. ↗
I suppose directing on set is the most fun because it's a good crack and you feel you're on the battlefield whereas writing is a fairly solitary undertaking. ↗
It's not easy to strap yourself down to a desk and bash on a keyboard when you know you can direct lots of films, because directing films is fun and interactive and gregarious. Writing isn't. ↗