Monitors Many monitors are still set to 640 X 480 pixel resolution with 256 colors. A great looking web page generated at 800 X 600 pixels and 24 bit true color, will look very different on a monitor set to 640 X 480 and 256 colors. You know what the average person will do, click, click. I'm outa here. Sixteen bit true color displayed at 256 can look just as frightening as left, right scroll bars.
Blue colors become purple, red colors turn orange, it's quite a different world.
It's a simple task to change your monitor's resolution and color depth, so do it and see how your site looks at various settings. You may be in for a big surprise. Adjust the resolution and then do a test run. What you once thought was a good web site may need adjustments . If so, make the adjustments to the page in this mode then switch back to the original settings.