In my experience, they last me at least 6 years. I bought my parents’ washer dryer in 2012 (Electrolux) and it hasn’t had a problem, and my LG stuff from 2016 is still fine. And I had babies, so we were doing washer/dryer loads almost every day, multiple times per day many days, and opening and closing the fridge and freezer all the time too.
I feel like the calculation is more like spend $1k to $2k for a machine with 80% probability of lasting 5+ years, and 50% chance of lasting 10+ years, or spend $5k+ for machines with a 95% chance of lasting 10 years. But the problem is the subzero does not come with a parts and labor warranty for 10 years, so might as well go with the former option, and replace it if it breaks.
And also, I am not running a mission critical operation at home where a broken fridge is going to drastically affect our lives (we have a 2nd in garage anyway), so why not take the gamble, and invest the extra money?
I always buy from Costco so that would have to be 16 years. I would rather invest the difference in cost and keep buying new every 4 years.