Like with everything else in life, it's not always about the mistake itself, but how it's handled afterward. Did we make a reasonable correction/adjustment or did we just say fuggit? Did we learn from our error???
FWIW, I had a piece of equipment that I bought on eBay. Turns out it was from our very own Nielsk. He was great about the problem although he never knew about it and it was definitely not his fault. Anyhow, I discover a MAJOR flaw in a PCB from one of the top pro audio manufactures out there. After numerous emails to said manufacturer, I finally got "oh yeah, one of the engineers remembers there was a problem on the Rev A boards". This problem was not fixable by cutting traces and adding jumpers. The board would have been destroyed in trying to do this. I told them that. They said nothing. A good reputable company would have said, "send us that old PCB and well send ya a new current one". They did jack shit about the problem. These things were so efed up they should have never left the factory. The boards were actually 100% unusable under certain situations.
This is the kind crap that does not happen here. Sure there will be problems. When they are found they are brought out into the open. Sometimes, numerous forum members have numerous different fixes. Everyone learns something (or more!) and we move on, enjoying our DIY gear!
I think overall, the projects 'round here are better than store bought...for many reasons!
Cheers, Jeff