Why does Tesla not manufacture the doors themselves? I would think such a special part unique to their cars would be first produced in house until all the bugs are worked out.
Modern car doors are usually sheet metal with a large amount of forming to give a shape (close to) what the designer wanted. It's difficult, large, expensive, and the knowledge required already exists in outside suppliers. Maybe someday they'll do it in house.
I recommend the book "Car"[1] about the redesign of the Ford Taurus twenty years ago. One of the topics is how hard it was to actually manufacture the (at the time) very complex curves of the exterior.
I don't remember where I read it, so I can't provide a source, but I thought I read somewhere that after this issue with the doors it is a goal at Tesla to try to manufacture as many components as possible in-house as their resources grow.
