Why I don't cruise on NCL anymore

Many people ask my opinion on booking a cruise with Norwegian Cruise Lines.  As a platinum member I have taken 9 cruises on Norwegian (NCL).  But I have stopped because for the last 4 cruises they have not met all of the 4 simple requirements I have for any cruise:
1. Clean
2. Basic Comforts (toilet, shower working), bed, cupboards etc not broken
3.  Safety
4.  Responsiveness to these simple issues (carpet cleaning, cabin issues etc.)

I have been on the Sun, Star, Pearl (2), Jewel, Breakaway, Spirit, Gem (2). 
- On the Pearl the cabin carpet was so stained/dirty, showing it to the assistant Hotel director he was so appalled he had it removed and replaced the next day.
- On the Jewel between the Carpet and lighting issues, they moved me to another cabin during the cruise, as the steward/hotel director recommended it
- On the Spirit, I had what I call the haunted toilet - it went off several times day and night for no reason. Yes they came to inspect and try things but nothing worked so they said they couldn't help. Plus even with a letter from Norwegian for an onboard credit, only after 3-days of revisiting the front desk (because it wasn't in their computer), the hotel director reluctantly agreed to honor the OBC. I even had to wait to get my pre-paid gratuities back via the mail.  Never pre-pay your gratuities - but I did because I trusted NCL.
- Finally on the Breakaway, cleanliness in the cabin, broken cupboard doors and non responsive, non communication re helping me just not get hurt in the cabin did me in ... no more NCL for me.
Did I try to communicate with staff respectfully - absolutely but NCL personnel are very hard to deal with so I just gave up. 
I have not had any of these types of issues or lack of responsiveness with Princess, Holland America of Royal Caribbean, thus why I have moved my business away from NCL.