I've found that most all artists (and we ARE artists) tend to be perfectionists. Look at some of our great inventors and scientists. How many light bulbs did Edison make before he got one to work? They won't quit till it's perfect. And it's not just in or quilting but in most everything we do. Remember, for the most part we sew to please ourselves unless we're professionals.
Our family and friends never see our mistakes or slightly off seams. Neither do strangers unless they're judging your quilt in a show.
So quilters all, relax, enjoy your talent and if you have to spit once in awhile, that's what the board is for.