I have worked as a Quality Control Manager for two different home builders but they had one thing in common. They wanted the homes built correctly...unless it took too long. Every time I said that construction on a home had to stop so that defects could be corrected, I had to argue with everyone from the Superintendent to the Project Manger to the Area Manager as to why it was necessary to stop progress on the home.
I usually won the argument. But that was only because I could show them sufficient defects. The point is that if it had not been for me discovering the problems (and being willing to fight to get them corrected), these defects would have been covered up and left until the new homeowner wondered why he had major cracks in his ceiling or his living room flooded.