Dashboard-light's data has much to say on the topic:
Just as an example, Honda/Acura lost a lot of points for selling an Isuzu on their lots for a while, and for the disaster that was their V6 automatic transmission during the early 2000's. How the crap did VW/Audi get a score like that?
I was under the impression older Beetles weren't particularly reliable, at least when you look at life expetancy. Sure, there weren't a ton of poorly built parts to fail, but how many 1500sp's (just as an example) are still high compression, burning zero oil and have needed no appreciable maintenance after 250,000 miles, as is common among modern engines? The plus side is (again, to my limited knowledge) that they're stupidly simple, easy, and inexpensive to fix.