So I'm trying to break in a new pair of shoes a bit today. They were pinching my toes a bit, but I thought I was OK, so I wore them to take a letter to the mailbox. I was fine for about 3/4 of the walk, and then suddenly, about half a mile away from home, my left heel was suddenly being chafed badly. I hadn't noticed any trouble until that moment. It's amazing how long a half mile can be when every step hurts.