Color must be used as a vehicle of expression rather than decoration. Poorly used color is worse than no color at all. Upon encountering your communication, readers will immediately begin responding to color even before they begin to notice your words. Appropriate colors reinforce your words. Inappropriate colors undermine them.
Color projects an image of quality.
The presence of color adds value to your communication. Readers place more value on publications printed in color. Readers associate color with importance. The presence of color signals that you consider your message, and your reader, important enough to invest in more publication preparation and printing. As a result, readers will respond by taking your message more seriously.