Is it public demand for continuing lower prices or stupid manufacturers trying to out sell one another and reducing the costs down and down!
There used to be some sound economic reasoning behind this. But it was more manufacturer-lead than consumer driven.
Look up W. Edwards Demming to see how the Japanese got the idea in the first place. Making products more cost-effectively is a good thing: Stripping out unnecessary costs and streamlining supply and production. What's changed though is the commoditisation of what used to be luxury goods. The pendulum swung too far.