"Certainly none of us serious writers of Latino origin wants to be a mere flash in the literary pan. We want to write good books that touch and move all our readers, not just those of our own particular ethnic background. And speaking for myself, I very much agree with the advice given to writers by Jean Rhys, 'Feed the sea, feed the sea.' The little rivers dry up in the long run, but the sea grows. What matters is the great body of all that has been and felt and written by writers of different cultures, languages, experiences, classes, races."
--Julia Alvarez, "On Finding a Latino Voice" from The Writing Life: Writers on How They Think and Work
On Deb's blog, she discusses the idea that a writer should, well, write for writings sake. Not for financial gain, not for recognition, not for awards. Writing should be it's own reward, basically. And I totally, totally agree.
I think it goes even a little further. I think it's like Julia Alvarez states in the above quote: we want to move people. What you, as a writer, have control over is the honesty and quality of your writing. So I say you should not only write, but endeavor to write well. Are your readers only going to be your critique group? Then try your damndest to make that group laugh/cry/scream with horror. Don't make it a half-hearted attempt. (This doesn't mean you can't turn in first drafts, by the way, as long as you've put thought and work into those first drafts. I'm not talking editing, I'm talking heart.)
This, in my opinion, is what 'feeds the sea'. Imagine if Emily Dickinson had gotten too disheartened by the one editor she'd sent her work to (which he sort of accepted at a point or two in her three-or-four-published-poems career) and had just stopped writing altogether? And I don't think anyone would call E.D. a 'little river'. Even if she wasn't published after her death, don't you think her family was not-a-little-awed by what they found?
So go write. And write what you want. And love it.