Why do laptop makers think no-one will notice whether their laptops work properly?

With the Apple results out last night, a number of clouds darken the iPod maker's horizons. Well-publicised are the options problems (TUAW) and the shipping of virus-ridden iPods (PaidContent); now Dan Gillmor points out that Apple also well have a lemon on its hands with the MacBook portable. The parallels with the credibility issues encountered by Dell for their lacklustre customer support (Buzzmachine) - and indeed the day their laptops started catching fire (SMH) - are almost too obvious to draw. There seems to be something peculiar to laptop-making that blinds the makers to the likelihood that their customers are all online and are going to make a lot of noise in public if the expensive, mission-critical stuff they sell doesn't work properly.