Once I heard a story about an artist who was asked when he knew a piece was finished. He replied, "When somebody buys it and I take it down off the wall." That's pretty much how I feel. I took a look around the studio at the recently finished paintings, and there's not a single one of them that I don't feel could use a little redrawing, or a slight color change, or a straighter line somewhere.
So, the one below has been bothering me. The right side of the tree just didn't look right, so I added some branches and leaves; I also painted some warmer leaves on the vines, hoping to amplify the sense of late afternoon sunlight: