Why are car depreciations not on a linear scale like any other piece of equipment?
It's the new car smell. Copiers are good for X thousand pages, tractors are hours of use based, roof wears out in 10-20 years. They perform similarly over their useful life, and then are basically worthless, and unless there is an accident before that life expires, they perform as expected.
Cars on the other hand, go rent something, I had one last week that had 300 miles on it, nice car. I've had some that had 5000 on the clock, and it was nearly trashed, interior rattles, scuffs on everything, nothing broken, just not that great. New, you know what happened to the car with the exception of what 12-15 miles, even at 2000, I've rented cars that I wouldn't dare buy, ignoring the brand or model, say I wanted that model, I wouldn't buy that one.
After 3-4 years, it falls back to close to linear, the car's on the flat part of the curve by then, just using up the remainder of the useful life.