Tesla seems to be taking the opposite approach to Apple here. In my observation, Apple drives its suppliers extremely hard to achieve the quality it requires. Tesla, on the other hand, is too eager to bring any sundry part in house (e.g. car seats). Apple's approach appears to work in that it pushes suppliers to do what's necessary. I worry that Tesla, having already bitten off a large bite to chew, is inviting too much distraction that will, in the long run, not put Tesla in a stronger position (there is a reason most automobile manufacturers outsource their seats after all).