"Yes, but how many hours of programmer time did it take to do the optimization, and how much money does a few hours of a programmer's time cost versus a few hours of a single CPU core?"
You seem to be comparing "expensive" optimisation against a single ruin of a programme. How do you think the numbers stack up when the programme is run every day for a year? Maybe it runs multiple instances for different users? Or it's a product you sell and it's run millions of times per day all over the world? So maybe it cost a few grand to optimise, but it saves millions of hours of CPU time around the world making your product that much more competitive than others so you sell more.
Biting the hand that feeds IT
