I sold my bmw after 15 years of multiple bmws because their design is so poor for maintenance. I had cooling system problems that required hours of labor to get to just to replace a plastic part that cost $5 where an aluminum one would cost $7.
It seems to me that bmw was designing for best case scenarios where everything goes perfectly. And since it’s supposed to go perfectly who cares if it’s $5000 to fix because it will “never break.”
Reminds me of Rube Goldberg software designs where 9 things have to happen in sequence for success.
The idea of rubust design that assumes everything breaks and you can still operate is one I value. I look for car companies (and everything I suppose) following this principle.
The problem is that $2 here and there adds up, and at the level of the whole car it can add hundreds, or thousands of dollars of extra cost for reliability that the user can't experience directly. For some percentage of owners the plastic part works fine for the whole time they have the car. On the other hand sturdier parts add expense in the case of an accident or replacing parts during routine maintenance.