I purchased these boots for birding outings on mudflats, so these boots should've been made for walking. The boots themselves are comfortable on my feet, but the tongue on the left boot is a killer. I had to insert a soft plastic strip; lace the boot so it laced up the side, not across, the boot; and wear extra heavy wool socks. I know the boot will need to be "broken in," but why was one perfectly fine, and the other was a killer?