Unfortunately, the people who pay us do not always view things rationally; in particular, they tend to be quite happy to rubber-stamp existing ongoing expenses, and very reluctant to authorise new expenditure, even when the new expenditure could reduce the ongoing expenses.

Or, to put it bluntly: in my experience, most PHBs would rather you wasted two weeks optimising your code, than spend $8,000 on a server upgrade.

Why? I don't know for sure. The optimist in me says it's because my salary has been budgeted for, and there's no room left in the budget for hardware. The cynic in me says that it's because they don't feel they have any control over schedules (everyone knows IT projects always run late!), but they do have control over the purse-strings, so they control what they can. Or maybe it's because they think that we're being lazy, asking for faster hardware instead of doing our jobs properly and writing fast code, and they don't want to reward laziness?

Really, heaven only knows. But it's a fact of life for some of us... and that means we do have to worry about CPU cycles, because even if they're irrelevant in dragonchild's Utopia of limitless upgrades, the real world is not so generous.