There is probably a cost consideration here. Every additional layer of supplier means more and more margin goes to them. I’d also imagine that if Tesla used th

There is probably a cost consideration here. Every additional layer of supplier means more and more margin goes to them. I’d also imagine that if Tesla used the seat suppliers that the rest of the industry does, they’d get lower priority in terms of access to seat designers, engineers etc. A company doing 200k vehicles a year in sales, split across 3 models, doesn’t really have much buying/bargaining power. When Musk visited Khan Academy for an interview some years ago, he mentioned that their USB cord supplier had shipped over defective cables, so they went to Fry’s to buy cables as a stopgap. I’d assume that kind of supply chain disruption is what they’re trying to avoid, for the more essential parts.