Walmart Boot Socks Continue to fail

Update to 5-7-12 Two more socks made it to their final resting place. Both exhibited the same failure mode as previous socks that failed. A hole seems to develop where the heel is sewn in. I found the socks to be warm and comfrtable, especially for the price, but it is somewhat disconcerting that they have all started to fail, and in the same way. I guess for $2.50 a pair I cannot complain too much. And I did get a year of wear or more out of them.

This one also shows signs of wear under the ball of the foot.