You have probably noticed when shopping for a TV that the colors displayed vary somewhat dramatically from one model to another. Although part of the disparity is due to the quality of the individual make and model numbers, much of the difference is also due to variations in the manufacturer's factory calibration settings.
You may like your monitor very bright, or the room you are viewing your files in may be dim. These factors and many more all affect your perception of color. In order to judge color consistency, we need to calibrate our monitors.
There are many tools out there to aid with monitor calibration, but one that is affordable and very easy to use is the X-rite ColorMunki display. It will take readings of the ambient light in your room, as well as your monitor to adjust your settings to display as close to a printed sheet of paper as possible.