Ex-Carnival and Royal Caribbean workers reveal the 7 most annoying things you can do as a cruise-ship passenger

"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."

"When they don't wash their hands after going to the toilet, or grabbing food directly from the buffet with their hands," a former Royal Caribbean Cruises employee said.

A former chef for Carnival Cruise Line and Royal Caribbean said failing to listen during safety drills was the most annoying thing passengers did.

"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."

"They behave in a way they would never do at home," said a former Royal Caribbean first officer who now works for The World, a residential cruise ship. "Like would you ever call 911 if the internet does not work or your toilet does not flush?"

Going to the dining room right before it closes is the most annoying passenger behavior, said a former hostess for Carnival.

A former waitress for Carnival said she was annoyed when passengers asked her questions they could easily find the answer to somewhere else, like guest services or an app on their phone. 

"I lost valuable time and money, since my income was based on my sales," she said.

• Read more:
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• Ex-Carnival, Royal Caribbean, and Norwegian Cruise Line workers reveal what they wanted to tell passengers but couldn't
• The grandfather of a toddler who fell from the 11th floor of a Royal Caribbean cruise ship is pleading guilty to negligent homicide to help end his family's 'nightmare'
• A lawyer who represents cruise-ship workers explains one thing passengers do that's terrible for some crew members