This is everyone's favorite excuse to trot out. But in reality the vast majority of projects I've seen never actually measure WHAT the performance cost would b

This is everyone's favorite excuse to trot out. But in reality the vast majority of projects I've seen never actually measure WHAT the performance cost would be and whether or not it's acceptable. So in the usual case the answer tends to be a mix of laziness and "that's how it's always been done."