Saturation describes the color's purity, intensity, and richness. Saturated colors are dense and vibrant and don't contain any gray. The bad news is that they have difficulty passing the WCAG (Web Content Accessibility Guidelines) color contrast ratio test. In turn, desaturated colors are likely to agree with the AA standard of at least 4.5:1 for color contrast ratio with the body text. Plus, they are more comfortable for the eyes against the dark background.