1 cent that is called damage, or PMD, Post Mint Damage. It looks like it got a heavy hit which ripped away metal to the side as you can see where it would go. Coins get used for currency. You'll find them in cash register drawers bouncing all around and getting hit by other coins. they get dropped, driven over in parking lots, used as a buffering in hammering (I do that, lol); stored up by the tonnage in purses, shipped by Loomis and other money transport companies in large heavy bags, etc. They are handled roughly over time. None of these examples are listed anywhere as non-errors because non-errors are endless.
