Sure, as an individual I can always buy a used car. But that doesn't change much globally: cars are generally driven until they're uneconomic. If not by me, the

Sure, as an individual I can always buy a used car. But that doesn't change much globally: cars are generally driven until they're uneconomic. If not by me, then by someone else. Put another way: if too many people buy new cars, then the price of used cars falls. There are enough people who compare the value of used cars vs new ones that a lower used car price causes them to prefer used over new. This is a fundamental feature of the car market, and that's why car dealers make it easy for you to trade in your used car.