I learn something from each quilt I make. Sometimes it is an intended lesson - like when I try something new and either learn how to do it or learn how not to do it. Other times it is an unintended lesson. But either way, I am constantly learning.
I don't know if that is a rule, but I was thinking about it yesterday when I thought, "Oh, so that is why you don't attach the binding that way!" It was too late to take it out, but I now know why.