when I was in college I spent summers teaching tennis in some tennis camp in New England. The owner of the camp always told this story every year of how his brand new Mercedes W123 was delivered to him missing a brake pad. He was really impressed that he got an apology letter from Germany, and they told him they were suspending the worker responsible for a week without pay or something...
there was some moral to the story, but I wasn't really paying attention. The missing brake pad stuck with me though! The moral of the story that I take from it is that where you have humans, you're going to have human error. That's life. Obviously, it provides fodder to hate GM, hate unions, hate the state of Michigan; some people will view any event though a lens which fits their preconceived bias. Personally, I'd be a lot more concerned about a defect in design or materials that was widespread, rather than one which affected 20 or 30 vehicles and is attributable to human error. Things happen. In this day of the internet, we're more likely to hear about them.