Turning around a cruise ship is an enormous operation, with a very precise sequence of events. Disembark passengers and luggage, resupply, embarkation of new passengers and luggage. My worry is to enter the process out of sequence, as it were - if you drop off your luggage before disembarkation is over, or before embarkation usually starts (I would think there is usually a space of time in between the 2). They could end up lost somewhere in the system, either with disembarking luggage or with luggage going to another ship.
The closest example from my experience that I can come up with is a flight we had to WAW on LOT, connecting via YYZ. There were 2 LOT flights that day from YYZ to WAW, and we were on the later one, but our connection arrived at YYZ before the first one left. When our luggage wasn't on the conveyor belt at arrival, I correctly guessed that it had been put on the 1st flight and was sitting in the back office with the rest of the unclaimed bags from that flight. Humans are used to certain sequences and routines, and have a hard time adapting to exceptions.