Someone asked whether two people could generate the same set of mnemonic words.

The possibility of BIP39 word combinations = 2048 ^ 12 (it can also be 15, 18, 21, 24; the higher, the safer). BIP39 passwords are customizable, and BIP32 paths are customizable. The combinations add up to an enormous astronomical number, thus the probability of two people generating the same set of mnemonic words simultaneously is like the probability of two atoms colliding randomly in a universe.