Andrew, I generally agree with your observations but I think you are mistaken that price is a factor when it comes to mistakes.
In other areas of human mass production lives are lost when mistakes are made. In our little world of choo-choo trains, weather its a 10.00 dollar flat car, or a 500.00 brass car, there have been and will be mistakes. Nobody wants to produce an item with mistakes, but it does and will happen.
Charlie