[jacobr1]

And similarly, nobody is paying for the blueprints, or CAD files, or assembly or whatever, they just want the car. There might be people that DO want those intermediate outputs (other car builders, hobbyists) but not the usual car-buyer, even one with very-specific needs.

The one exception to this might be, the car-buyer that does intend to heavily modify their vehicle, might value to the availability its creative inputs so that modification later on is easier.