All good answers. I think the one that fits me best is Toni Morrison's quote: "If you find a book you really want to read but it hasn’t been written yet, then you must write it."
Another thing about writing. I may have a story to tell, but it really doesn't gel or coalesce until it put it on paper or on the screen and see what it is that I've produced. I find that once it's there, it usually doesn't truly reflect what I wanted to say. So I change things here and there until the thing on paper/screen more accurately reflects my thought. The printed word is my tool for that process.
I read somewhere about an author who described his writing process as trying to take down a story heard on a radio with a lot of static. They take down the story as best they can, and then try to make sense of it, correcting some words and adding others into the gaps, until a coherent story emerges. Sometimes I feel like I'm doing that.