If you turn the razor the wrong way while stropping, ie turn it so the edge stays in contact with the strop rather than the spine, then you're bound to roll the edge. "Rolling" being to bend the edge with direct pressure so the very leading part of the edge, probably only a small fraction of a millimetre, is no longer straight in line with the rest of the blade. If you do it repeatedly you'll be bending the edge back and forth and it'll behave like any other piece of metal that gets bent back and forth and break. That's bad mojo. You can also do it by putting to much pressure on the edge while stropping or not having the strop taught so it sags badly.
Lifting the edge off the strop while it's still moving opens you up to the possibility of putting the edge back down on the strop travelling the wrong way and that's just going to go badly.