Why Do Writers Write?

Patricia Hampl says that she writes in order to find out what she knows. Which makes some sense to me. Sometimes when I write, I found out things about myself that I either didn't know or hadn't formed a definite opinion about. But I think a lot of what I write comes out just because I have an overactive imagination. Something someone says or does, a moment I experience, or something I see will trigger a reaction in my brain and I start imagining scenes and storylines.

I often wonder why other writers write. Do they also have overactive imaginations; do stories grip them and refuse to let go until they're recorded on paper? Or do they write because it's something the desire to do, and so they work at it. Are there writers who couldn't care one way or another, but write because they've discovered they're good at it?

People like Steven King, my personal favorite Dean Koontz, or any other well-known author.... I wonder how they got started, how they got their big break, and if writing is more business or pleasure for them. It's pleasure for me, but if I can turn it into business, that would be great too! I guess maybe it's kind of like when actors take on certain roles because it sells/pays, but prefer other, more artsy/indie kinds of roles.

I guess I'm really wondering if all writers feel the same need to write that I do. For some reason, when my mind/imagination wanders, I feel compelled to capture and develop the resulting ideas on paper. A lot of times I don't even worry about whether it's publishable/marketable, or if it could become anything more than what it is at that moment (although I'm trying to focus more on that so I can get something published.) A lot of times I'm content to write down what's popped into my head and leave it at that; just the sheer act of capturing it somewhere permanent, so I can revisit it whenever I want, is almost satisfaction enough.