It's purely economics for us (we buy what we can afford, as do many others). In one of Clark Howard's shows Ii'm not sure if he's on CNN currently, but he used to have excellent shows about all kinds of financial things), he talked about car insurance.
It never really dawned on me, until I saw this particular show, just how much difference in insurance premium rates there are between a brand new vehicle, and one that is 1-2 years old, or older. He was saying that you can get a very good used car (with carefully researched buying, etc.) for a few, (or more), years old; and the insurance drops dramatically. That completely changed my view of used cars. Prior to that, I thought you should only buy a new car.