I retired from production at GM after 30 years and I can assure everyone people on the floor, those actually doing the work, used to get really frustrated about this kind of thing. This isn't uncommon at all, especially in parts plants. There's always a push to make schedules and if comes down to a decision to stop the line and fix something or keep running, most times keep running wins.
This isn't something unique to GM though. All car manufacturers, domestic or foreign, deal with this. In fact, all manufacturers period deal with this. I'd bet my bottom dollar someone at a very low level, very early on, alerted the higher ups about this and they were ignored.
This hits close to home for me because over the years I've seen the blame for this kind of thing shifted to those "lazy, greedy, over-paid, workers" when they aren't the ones making the decisions.