The fail rate for Bosch (the stuff I install/sell) is listed as being around 1 to 2 percent maximum. Any electronic manufacturing industry usually operates around 3 percent if its a quality product.
I think the prechecks would have saved alot of this if they were done. If they were offered etc.
I know its easy for people to want to execute Stern for warranty hassles etc, but its just as easy to be realistic and understand all this is normal for any industry if we are honest. Cars, motorbikes, whitegoods, anything and everything, even brand new Jumbo Jet aircraft have warranty and fail rates.
Can Stern do better, ofcourse, and i am sure they are working towards it.
None of us like it, but welcome to technology (or lack thereof) and to having humans help stuff it all up.
Things can only get better, but the perfect pinball machine will never happen, until Terminator 3 robots take over the planet.lol