It turns out you're right, but that's old information, and more recent information does not make the same conclusion.

The most frequently cited authority on vehicle dependability is J. D. Power and Associates, and they are the resource that was quoted by Reader's Digest. They rank all the car makes, and publicize the rankings of those above the industry average. In their 2000 survey, which you can see here, Porsche indeed finished second. However, in 2001, which you can see here, the top five makes were Lexus, Infiniti, Jaguar (surprisingly IMO), Lincoln, and Acura, and Porsche finished ninth - still not bad, but no longer in the top three, and not as good as Acura or Honda. Porsche was not listed in the 1999 survey.