I think it’s a mixed bag. There’s obvious efficiency in having a small number of companies make parts and sell them to the many auto makers. There are obvious d

I think it’s a mixed bag. There’s obvious efficiency in having a small number of companies make parts and sell them to the many auto makers. There are obvious downsides to outsourcing too. I think Tesla is a good illustration. They make a lot of parts other auto makers outsource, and they also have a whole lot of quality control issues. I am sure I suffer from observational bias here, as my GF has a model Y and I notice all the parts that fail that never would on any other car (like vent fans, door handles, etc.) but the upside exists in some engineering document or p&l I don’t see.