Farming out to the lowest bidder works well when the guidelines are strict and the client (gvmnt) does good QA.
Lots of stuff was farmed out in the apollo mission and it was still ok. Strict QA was noted as a very important factor in why that mission was a success.
You can read the case study by NASA about this, and you’ll see that they have 1 article just about QA and how they did testing, and another one about testing and deadlines