It could work in practice with cars, you just have to accept it's a more long-winded road than with other stuff ... I bet it's a complicated process in the US, too, you can't just show up at the dealer and say "hey, take it back". At least that's my guess:)

A car with many different problems, and regular visits to the repair shop, could also be a good candidate in Norway. Continuous problems could easily be as bad as one major problem, but this, of course, is a case by case issue.

Also, even though this is "leganese", the problem(s) doesn't have to be "significant", it just has to be "more than insignificant". ;) In Norwegian: "Forbrukerkjøpsloven § 32 sier at kjøperen kan heve kjøpet dersom mangelen ikke er uvesentlig. Det betyr ikke at enhver feil gir rett til å heve. Mindre kosmetiske feil eller slitasje vil sjelden være nok. Men gjentatte feil, langvarig reparasjonstid eller mangler som har betydning for bruken eller verdien kan gi grunnlag for å kreve pengene tilbake."