I'll start by saying I've been on 8 Princess cruises, 3 NCL cruises, 1 Royal Caribbean cruise, and 2 Carnival cruises. Of those 14 cruises, only two have ever canceled ports altogether. Those 2 were both the Carnival cruises I've been on, and the biggest reason I'll never go on Carnival again.
This cruise was something our family had talked about doing for 13 years, and had actively planned for nearly 1 year. We were excited about going on a new ship, but the overwhelming reason for choosing this cruise was the fabulous itinerary, and the fact that out of 11 full days, only 3 were going to be "fun" days at sea (a better ratio than any cruise I'd ever been on). When all was said and done, only 5 days ended up being in ports, and 6(!) days were at sea. The trouble started the morning of the first full day, when during breakfast in the dining room (which incidentally we walked out of after being ignored for over ten minutes after being seated), an announcement came over the loudspeaker saying that we would not be able to dock in Monte Carlo due to high winds "for our safety". The odd thing is that the wind was less than 10mph, and the seas were calm. We later heard from other passengers that Monte Carlo had been canceled on the last two cruises before us, and that our captain had crashed the Breeze into some expensive yachts in Monaco on a previous cruise, and they had decided beforehand not to return again. Whatever the reason, it was NOT the weather, and it had clearly been decided beforehand. Later that same evening (after the first unexpected "fun" day at sea), an announcement was made that "Mother Nature was STILL not cooperating" and many of our big ports would all come packed together at the end of the cruise, and Messina (Sicily) would be omitted as well. The next day we stopped as planned in Livorno, then had two more unplanned days at sea before stopping in Dubrovnik. That night, after leaving Dubrovnik, another announcement came. My husband and I were eating in Cucina del Capitano at the time. This announcement was to tell us that they were "so sorry" but the weather was yet again an issue, and now we would not be getting EITHER of our TWO days in Venice (however the one day in Messina was mysteriously returning to the itinerary). After this third announcement canceling Venice, all hell broke loose. The couple next to us in the restaurant was on their honeymoon, and the wife began to cry. My parents were in their stateroom at the time, and they heard someone scream with rage in the hallway. An angry mob started to form at guest services (later moved to the theater due to size). Crew members took names and contact info, and implied that things would be made right (to date, over a month later, no one in our party has heard a word from anyone at Carnival). The compensation for radically altering the trip we all had planned on? Refunding $40 in port charges, and one free drink voucher good only in the dining room and for a limited selection of drinks.
Other aspects of the cruise were disappointing as well. Food was definitely subpar, both in the dining room and the buffet. Meals were often served cold, and missing certain ingredients (no cheese in "broccoli cheese soup", no sweet chili sauce on "thai sweet chili shrimp"). Parts of the buffet were often inexplicably closed during peak times, leading to overcrowding and exceptionally long lines in areas that were open. The dining rooms were frequently closed for breakfast and lunch on the "fun" days, leading to even more people at the buffet. The one bright spot for dining was Guys Burger Joint, which had exceptional hamburgers and oddly enough not much of a wait most times we went there
Entertainment was very limited. On a 12 day cruise, only 4 shows were provided, and they were just repeated continuously. Most of the entertainment options that were heavily hyped cost money (bingo, thrill theater, casino, etc). The constant announcements to encourage passengers to take part in these paid activities was enough to make more than a few people skeptical of the real reasons of all the added "fun" days at sea.
Being a new ship, everything was very clean, including cabins. Beds were not comfortable, and didn't seem any different than on the 8 year old Carnival Miracle we sailed on the previous year. Our particular room was right across from one of the only TWO laundry facilities on board, which seemed very inadequate to handle the needs of nearly 4,000 passengers. This meant that every day from 6am until midnight, there was a continuous line of people spilling into the hallway waiting to do laundry, some of whom actually sat in our doorway and fell back into our room when we'd open the door. I'd advise anyone to look at a deck plan map carefully before booking.
This cruise has basically taught us that you get what you pay for. Before going on Carnival, I wondered how they were able to charge less than other cruise lines and stay in business. This cruise answered that question all too well. Subpar food, more passengers per unit area, canceled ports, and limited "free" entertainment. We won't be going on Carnival again.