I'm a huge fan of the Ira Glass talks on storytelling.
In the video I've embedded above, Ira Glass talks about one of the biggest problems with submissions he receives for his show:
The person has a horrible personality.
Who are people with horrible personalities?
The ones who only seem able to talk about themselves.
Herein lies, I believe, one of the great secrets to being a writer: You are curious about others; you are curious about the world.
To be interesting, we have to be interested in other people. That's how it works.
(If this doesn't describe you? Fake it for a while until it does.)