I used to get so frustrated when I would make a mistake in the early days. I would rip and re-sew and repeat. There were a few "errors" I just couldn't improve so I left them in. When the quilt was finished (quilted, bound, and washed) I was not able to even find the issue that had give me such heart burn. Now, I KNOW what is an acceptable fudge-factor and what I can live with and move on.
When we work on a quilt, we are so close to it (nose to the stitches) and it is easy to lose sight of the big picture. NOBODY is going to take their quilted gift and examine it for flaws (and if they are, they don't deserve the gift). We are often way too hard on ourselves.