ELI5: Why do elevators do not all activate at once and race down to the floor they’re needed?

There was a LOT of people waiting at the hotel lobby I was at with 4 elevators that could only fit 11 at a time. We were in line and it took 30 minutes for us to be able get on one.

All were operational to my knowledge, but only two out of the four seemed to be coming repeatedly at the lobby to pick us up (the other didn’t move from their floors).