In my mind, that's one of the great things about self-publishing. It gives you a chance to experiment. Sure, you might fall flat on your face, but as long as you're able to handle the loss financially, you can move on and try again with another book.
And sometimes your experiment might just be successful.
I think that's the appeal to most people. I've always thought failing on my own terms is preferable to endless rounds of querying, form rejections that can be interpreted a thousand ways, stony silence, full requests followed by "not for us"...