There's an expectation that the price / performance ratio also improves as time goes on. Put another way, you should be spending the same (plus inflation) ever

There's an expectation that the price / performance ratio also improves as time goes on. Put another way, you should be spending the same (plus inflation) every few years, and getting significantly more bang for your buck. I haven't done the maths, but I guess a lot of people are not feeling this.