When I worked as a cashier in a grocery store many years ago, someone gave me some checks to pay their bill. I didn’t even look at the damn thing, just inputted the numbers it said and started running them through the check machine. It seemed to go through the machine correctly.
But just then the manager ran over and stopped the transaction. They were fake checks.
I guess silly me assumed things would just automatically not go through in the modern age, but I guess it showed me that I really have no idea how check machines like that work.
Still don’t, but I don’t work that job anymore so it doesn’t matter.