I don't know about Germany, but The Netherlands has a significant market for second hand cars, and many cars, including German ones, are sold for serious amount

I don't know about Germany, but The Netherlands has a significant market for second hand cars, and many cars, including German ones, are sold for serious amounts of money when they are 10 years old. It is instructive to go to scrapyards. Typically many parts of a car are quite cheap. Some parts has some sort of design error and fail in almost all cars of the same model. However that varies from model to model and from brand to brand. Of course, the lease market prefers low maintainance costs. So it makes sense for manufactures to optimize in reducing those costs during typical maintainance periods. But that does not imply that after 5 years or so, maintainance is suddenly sky high.