Such as guarantees, recalls, offers, campaigns, financing, leasing, standard maintenance, buying original parts, upgrading software, downloading GPS maps, resetting the addblue, refilling your particle filter liquid, changing belts, buying extra power for some time...
I thing that the term is pretty self-explainable. Every support that the customer could request from the brand after the sale. Some of this things can be provided by anybody, other only by the brand.
Most of these can be provided by any car shop (usually a lot cheaper than the manufacturer) and you don’t need to involve the manufacturer and rest are not things any normal person cares about.
But not all. I had never meet a single car owner that spend solid money in their new car and then decline the maker guarantee, but your definition of what is "normal people" may differ from mine.
Thinnest of fucking arguments. Sure if there is a mechanical fault and you get your shit replaced, but are you really arguing that you shouldn’t hack your infotainment fir the off chance that your car has manufacturing defect?
You definitely do not need to go to the manufacturer for oil change. If you can’t change your cars oil yourself you can go to literally any car shop to get it changed for pretty cheap