This is great advice for almost any field, and you have shown it in such a beautiful manner. This was a wonderful read, and you are an amazing painter.
When I write, even I think the initial product is beyond lousy. Having been in that place more than once, I now have a very effective system arranged. I take three hours in a day, in fifteen minute periods, to write blindly, without giving the screen a single thought (quite difficult to do), and then revisit the work in a day or two, having written others in the interim. It helps me come back to the previous with fresh eyes. And usually, it isn't all that bad ;)
RE: About the destination. Begin, continue, stop and go again