No negative Nellies here, but we did have things wrong on some cruises but they were rectified and we’re happy. Things happen everywhere, not just on ships.
Twice the room safe didn’t work - one needed new battery in the keypad, and another got replaced.
One morning on Epic I stepped into the flooded toilet cubicle but held back and reported it to the room steward on our way to breakfast (with a stop in the public toilets). It got rectified within hours.
Last month I saw the video made by the guy who complained about the blocked/overflowing toilet .... little did he know that we spotted the culprit in the video - a packet of wet bum wipes laying on floor next to the loo!! There are signs and instructions saying NOT to flush down anything except for the toilet paper provided, and that includes the flushable items that can be flushed down in your own toilet at home, but not on ships.
I do not like to read the reviews made by people who complained about one or 2 negative things that happened to them during their 7 to 20 days cruise and have nothing else good to say.
Food is very subjective - on all cruises we like the food yet some other people didn’t like the same food we liked.
So read the bad reviews at your own risk! Sometimes I laugh at some.