Writers often wonder, "Why bother?" Writing is SO hard. It requires discipline, insight into human nature, willingness to bare one's soul, and choosing to put one's labor of love out in the world for total strangers to pass judgement. However, as Mr. Miller points out, "Writing is its own reward."
Once the first, and usually bad, draft has been edited, rewritten, and fine tuned, we read our work with satisfaction, and perhaps a bit of surprise, that it's actually worth reading. Even if we never feel completely satisfied with our work, writing is a wonderful catharsis. It helps us gain perspective on our situation, our relationships, and our lives, and THAT is reward enough.