I became aware of this problem when it happened to me.
I've had my lightning cable get completely stuck in the USB port of my pc. When I say stuck I don't mean a bit tight, I mean completely locked into the port. I almost destroyed the cable getting it out before I found this thread
on Apple's support forums and tried the paper trick to release it. It seems the 2 indentations on the bottom of the USB plug are too deep causing the retaining pins in many USB ports to grip the plug and lock it in place.
This it seems could become major issue for Apple. I'll be visiting my local apple store to try and get a replacement. Mine still works but I've made a mess of the plug trying to use pliers to release it, and that didn't work.
It may be worth posting this to the main page so people can see the fix to release the plug without destroying the cable.