Remember, people use coins for all sort of things. Do not let your limited imagination limit how it could get damaged. Coins in many instances are cheaper than washers and thus get used in a quick solution. There's a bunch of coins sitting in one of my tool boxes. Maybe I'll smack a few with a hammer and release them to the wild ... just because .... maybe it was accidentally dropped in some machine ?? The best answer is from the person who was correlated to the damage to know exactly what caused it.
You could write a book on "Fun with Coins" on how many different ways coins can be abused and damaged. Let your imagination run wild. "While at the zoo, Tony thought it would be fun to see if an elephant could bend a dime in half with its foot." LOL
Knowing exactly what occurred to the coin is less important than knowing it did not come out of the US Mint like that.
This would have to be the first time I've ever been told my imagination was limited. Being a yoga instructor/preschool nanny, and having an extreme passion for writing, I'd have to disagree with your matter of opinion. Why do you think I asked the question in the first place? To receive a plethora of possibilities. It's all good though. P.S. it had been wedged between two floor boards for many years. That's how it ended up this way. Boom!⚡