It’s my understanding that mass produced items are all basically the same. If you buy something like a toothbrush, for example, then any other toothbrush from that same assembly line is going to be basically the same and have all the same specs (with the exception with minor defects here and there), because the machinery and process to make any those toothbrushes are all basically the same.
But that can’t be the case with locks and keys. Because if every lock and key were the same then there’d be no point in having them. Anyone could just bought the same key/lock combo could use it to unlock your front door. So all or most keys and locks must be unique. So how are they mass produced in a way that preserves their uniqueness?
Im pretty sure its like hardware mac addresses and there is a lot of variety but not endless. Im like 99% sure a key from a lock can open a bunch of other locks sold but its really unlikely to open a lock sold at the same store. Anyway as for the how our modern mass production machinery has electronics and can be programed to things a bit differently based an a database or some math or such.