One thing I learned the hard way: STEP BACK AND ADMIRE YOUR WORK! That's when you find those little things that can be fixed easily when it's a block, and almost impossible when it has been quilted. Look with a critical eye at the blocks, the rows, several rows, the completed top and each border as added. Takes a little time, but so worth it.
I also found that someone will finish that UFO that you just don't like anymore. I won't throw it away.