Apparently part of being an artist is a constant struggle between the feeling of not being artistic enough on one hand and not being appreciated enough on the other; ideally, those two would overlap, pushing boundaries where necessary, and being appreciated for exactly that, but even when that is momentarily the case it would be too much to ask to actually realize your luck at the same time.
To some extent, we all, genetically, I believe, are artistic. Humans never simply shit on a plate, we have to give every pile some sort of meaning. Finding meaning in piles of shit is our specialty, our heritage, our destiny. "We are the makers of music, we are the dreamers of dreams", and we are the ones who see a smiley face in a dog's turd.
Thus we also are always aware of our shortcomings, struggling between the urge to rationalize them as a mere illusion and accepting them as a force of nature. Either way, they are that, a force, something to keep us down. While we can accept some of them, others we loathe, spending big parts of our lives fighting them, only to succumb eventually anyway. That is perhaps what is called the human condition, the ever failing unsuccumbment to being just another piece of life.
So we create, to influence, if not the world, then at least our peers, and if not our peers, then at least those we think are not as smart as we might be; all of this happens, of course, not out of malevolence or mischief, but because we want to matter. We, the artists, are those who can not accept that they don't matter. And if we can't matter to the cosmos, as we never can, then at least we could matter to those we think equal.
Creators create, perhaps, because they are incapable of inventing. We scribble leonardesque flying machines in our notebooks because we know very well that we shall never fly, we portrait the world around as we see it because we lack the words, or use the words because we lack the painting skills.
Art is never more than expressing what moves you. If you're lucky, it becomes a language, a bridge to other people's version of solitude.