Comment by AnthonyMouse

I would suspect that "hardware breaks over time" is a minor component of the cost. If you put computer hardware in a climate controlled environment with conditioned power, generally >90% of it will still be operational after a decade, with the expected replacement of wear items like fans and drives. To the point that the fraction of older hardware that fails will typically be smaller than the fraction you would replace for efficiency reasons regardless, and wouldn't be a large proportion of operating costs even if it wasn't.

Exceptions naturally if you for some reason had an abnormally high failure rate, e.g. capacitor plague.