Spending too much time at ports
"What's the most annoying thing passengers do? Not paying attention to the time they had to be back to the ship when in port," said Chad Stone, a former production manager for Seabourn Cruise Line.
"This was a massive deal because we would end up paying more in port fees if we stayed too long, or we would end up having to wait for larger ships to leave, putting us in a large queue of departing ships. The captain would have to make up for it en route, making for a bit rougher of a ride to the next port."
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Bad hygiene
"When they don't wash their hands after going to the toilet, or grabbing food directly from the buffet with their hands," a Royal Caribbean Cruises employee said.
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Not listening to safety drills
A former chef for Carnival Cruise Line and Royal Caribbean said failing to listen during safety drills was the most annoying thing passengers did.
Messy eating
"Younger [passengers] usually take food and beverages to their cabins, leaving a trail of crumbs and debris along the way," said Aida Carvahlo, a former human-resources manager for MSC Cruises, Viking Cruises, and Holland America Line. "After eating, they leave plates and glasses through the hallways of cabins. Housekeeping staff sometimes find rotten food under beds."
Acting in a way they wouldn't at home
"They behave in a way they would never do at home," said a Royal Caribbean first officer. "Like would you ever call 911 if the internet does not work or your toilet does not flush?"