In Germany the trades are very strong, have been so since medieval times. Build a house and tons of different trades have to come in, each with their own area of expertise. Not like here where one carpenter can basically do the whole thing
Not surprising they tend to leave stuff like battery changes to 'the experts'
I lived there one winter and changed oil, hoses, various parts myself on the old POS car my gf at the time was driving, it was thought to be odd, very 'British'.