Originally Posted by Nightshade

Basically because the color representation on 99% of PC laptop screens lacks the ability to show a "true range" of the color spectrum or proper contrast. It just isn't within the scope of their ability.

Add to that the fact that even if you tried you would never be able to adjust the screen to exactly the right angle every time you opened it to use it. even sitting in the same location the screen slowly (mostly unnoticeable) lowers whichever way gravity pulls it.

Also the screen adjustment programs on laptops is geared towards "acceptable" representations of color. Include backlight or lack thereof and you add an infinite number of variables you cannot adjust for every time (even with a no glare screen).

My editor does all his work on a Mac Powerbook, I took an image he adjusted and put it on my color calibrated PC at home and was surprised at how accurate it really is under almost any condition. I have calibrated my laptop a hundred times and it just never stays accurate for very long at all.