Being a trying to conform perfectionist, I would probably already know there was a mistake. My luck would be that someone found one I hadn't noticed and that would upset me and I'd probably never display my quilts again. I figure that if a quilt is displayed without mention of asking for advice the quilter is proud of their sewing and is looking for confirmation that a good job has been done. Pointing out mistakes even when done to be helpful should be done in private.