Testing cars in the "old days" clearly was different. But what the journalists of the magazine "Hobby" did was somewhat extreme. They went out to actually buy the test cars and then they did all kinds of tests with them to simulate what "normal" customers would experience over maybe a year of driving. They even took the cars to a race track (Solitude) and did 100 laps with them. And you have to know that it was about a Volkswagen Beetle/Bug, a DKW F12 and a Fiat Europa - family cars basically. Well they also did highspeed tests on the German Autobahn - knowing that these cars barely could reach 120 km/h. And at the end (after 5'000 - 10'000 kms) they took them apart to see how the engine looked from the inside. Finally they sold the cars again to see how much they would get.
If you are wondering what the result of the test was, then I must say it's somewhat difficult to say, as five journalists came up with five results. But more or less they liked the DKW best and nobody really put the Volkswagen at the top except for reliability where the Beetle really was the benchmark. The Fiat was at the top with one journalist and in the middle with three of the five. All in all they were quite happy with the quality, comfort and usability of the cars it seems.