I have sat in judging day for our shows, we have NQA certified judges. Every year they emphasize on the binding, no kidding !
Binding- can not be to wide, or to narrow. filled with the batting,the corners secured down and mitered. stitching can not show. you want to machine it to the front of quilt and hand sew to the back. They really like bias binding. Make sure your boarders are straight so your binding doesn't look woobely.