When a manufacturer outsources, It frees them from a lot of employee/employer relationship issues - many of which become vendor/purchaser issues.
A lot of managers prefer the relationship of purchaser to vendor, for a couple of reasons which aren't so nice. First is the fact that there is much less of a collegial relationship with a vendor than an employee. I can tell you, from 35 years as a machinist (outsourced, restructured, leased, temped, harassed, and generally screwed over) that the finance and marketing people HATE pushback from the technical side of things. They literally do not want to hear it - even if the pushback makes/saves significant $$$$$$.
The second issue is about who has power within the management structure - the purchasing function becomes much more important with outsourcing, as does finance. A lot of detailed engineering work ends up at the vendor as well, so there are fewer of those nerdy engineers around the office, and if the vendor's engineers have to deal with their customer, they have to be prepared to kiss a mile of ass! American engineers and skilled trades are not shy about telling the "suits"that their expectations are unrealistic, or, to be blunt about it "Hey, you guys fucked the dog again on this one!" A vendor will jump through hoops and bend over backward to keep the suits from finding out how badly they fucked up.