There are several reasons. First of all, cars that old usually have a quite used up interior even to the point of being unpleasant. But the big thing is mainte

There are several reasons. First of all, cars that old usually have a quite used up interior even to the point of being unpleasant. But the big thing is maintenance. If you can't do repairs on your own and with cars just 15 years old that gets increasingly more difficult, maintenance and repairs will kill you. At a certain point the upkeep will exceed the amortised costs of buying a new car.