We got well over $80k into manpower on optimizing our self-hosted app for resources so that we didn't have to tell less than a dozen big customers to upgrade their hardware before people stopped laughing right in my face for suggesting we just buy them some new rackmount equipment as a gift...
That project died the following year, and I believe the opportunity costs of that work were substantially responsible for the demise.
Lol, I do this. My customers would often try to run my software on dusty old servers and then complain that it's slow, so now I just send them the hardware for free.
Different team, we did a cluster install and they were getting 10% of our advertised transaction rate. Something was clearly off. I commented “did they plug the whole thing into a 10Mb hub?”
They had. We sent someone eight timezones away to find that out.
That project died the following year, and I believe the opportunity costs of that work were substantially responsible for the demise.