I always wondered about this one, you hear it a lot:
"A little less contrast
Black on white? How often do you see that kind of contrast in real life? Tone it down a bit, asshole. I would've even made this site's background a nice #EEEEEE if I wasn't so focused on keeping declarations to a lean 7 fucking lines."
But my monitor is not perfect, nobodies is so why make stuff less well readable, I don't understand it. It annoys me to no end when I have to copy paste stuff into a text editor just to get a white background because someone decide a background should never be white and people seem to agree. If I want less contrast I'll tone down the background lighting of my screen.