CAUSE: Possible causes of poor hiding include over-extended spreading, a radical color change, uneven application, excessive thinning, or inadequate mixing of paint. Certain colors such as yellow, red, and orange tones inherently offer weaker hiding.

SOLUTION: Most paints are designed to be applied as received. Thinning, if necessary, should be at a minimum. An additional coat of the same material and color, applied with a good quality tool at the recommended spreading rate, will usually provide good hiding. The exceptions are extreme color changes, extremely porous surfaces, and certain deep, clear colors. These require a prime coat tinted to the approximate color of the finish coat. Benjamin Moore color chips and color cards use a triangle symbol to identify deep, clear colorst hat require a tinted deep base primer to obtain good hiding. Don't forget to follow your dealer's recommendation for type and size of applicators and purchase good quality tools.

Above article reprinted by the kind permission of Benjamin Moore Paints.