I've noticed that people frequently place a huge emphasis on high ISO performance on DSLR's, then these same people pair their camera up with a f/3.5-5.6 or other slow lens.

Something counterproductive there, sort of missing a piece of the equation. I wonder how many people base their purchase decisions on high ISO performance, then keep a slow lens attached to their camera.

It is frustrating to see people fall into this error of judgment. I also don't know why I care, but it just irks me. Anybody else share this frustration?