Don't laugh, but I made the same mistake most guitarists make. Sure, I wound them the right way, but sometimes I had an excessive amount of string and failed to lock the loop.
Years ago, I was at a worship conference at a local church. Again, don't laugh, but a former member of Air Supply, David Moyse (I think that's his name), was giving a lecture at the conference. He randomly picked me out of the crowd and asked to see my guitar, and then proceeded to restring it using the locking loop technique.