Why write fiction?

I've been thinking about why I turned to fiction.  My textbooks have been successful so why didn't I prepare a 4th edition of one text and a 2nd edition for another?

1. Writing fiction is a new experience for me.
2. In retirement, I  needed to do something different, something new, in order to keep my brain engaged.
3. Fiction involves powerful and significant ideas outside of the context of academic fields.
4. Fiction causes readers to think and to feel; it's both cognitive and affective.
5. Fiction is entertaining.