Pool hours

Can someone explain to me why do both ships, QE2 and QM2 have such draconian
pool closing times. We sailed on QE2 when she was with Trafalgar House and we
practiced our diving in the small ours of the morning, but not now, now it's another lost benefit because of Carnivalization. They use the old "safety" excuse, not that anyone is
worried about safety at anyother time or they would have a lifegard!!! It's 89degrees in the Caribean at 11 pm and we are up on deck, but the pool is closed. My cabin does not have a pool...so what gives? Give me a good genuine excuse...