I was on a Royal Caribbean ship a couple weeks ago (Utopia, 18 decks, 5,668 passengers). It has 24 main elevators split between front and back, left and right.

I was on a Royal Caribbean ship a couple weeks ago (Utopia, 18 decks, 5,668 passengers). It has 24 main elevators split between front and back, left and right. So a bank of 6 in front of you each time you needed a lift. You press your floor on a touchpad and it assigns you an elevator A through F. I swear no matter if it was busy or not, it seemed like everyone was assigned to the same one or two elevators. The wait was always so long too, I used the stairs most of the time if just going <6 flights. Someone besides RCCL needs to study that algorithm.