CRT [cathode ray tube] monitors have a red, blue and green "guns". If one of the color guns burn out, the color is gone from the entire screen.
If it is gone from part of the screen or otherwise varied, you are magnetized or "gaussed", pulling the red beam off to one side.
Many CRT monitors automatically "degauss" when you turn it on. Some have a button or menu option to manually degauss.
Sometimes the aberration is caused by a strong magnet (speaker) being too close to the screen, playing sounds too loud, therefore large magnetic flux, and color distortion.
LCD monitors don't have this magnetism sensitivity, but little portions on the screen can burn out. Look at the longevity of laptop screens. It's usually the 1st (and most expensive) laptop repair...new screen.
Flat panel LCD monitors don't have enough customer use time yet to see some pattern and longevity to burnout, especially for different brands.
My monitor has partially gone out, with the red missing (most of the time, and mostly on the right side).
I was thinking maybe getting a LCD next time, so there would be one less thing to worry about. Or would there?