Which is why they tend to move to larger modular components. Things like seats arrive preassembled and simply need to be inspected and installed. Inspection can happen off the assembly floor and managed without disrupting production.

> You have to trust that the 3rd party supplier is meeting the required spec in manufacture and that the parts are damaged in transit.

You don't have to rely on 3rd parties to run an assembly plant. Your assembly plant can be fed by your own manufacturing facilities. But if you do rely on 3rd parties, it's definitely possible and companies like Apple do it with great success.

The quality of passenger cars is so, so much higher now than prior to the use of these methods. It seems like they've got the quality control processes taken care of to some extent.