Premature and/or excessive lightening of the paint color, which can occur on surfaces with sunny exposures. This is relatively easy to see because hidden areas such as eaves will not usually fade. Fading/poor color retention can also be a result of chalking of the coating (e.g. primer, paint or stain).
Colors will fade slightly when exposed to intense sunlight. As the coating ages, the fading can become more noticeable. Slight fading is acceptable, provided it is gradual and uniform so as not to be noticeable. Excessive chalking of the paint film will cause colors to appear lighter.
Interior-grade colorants used outside will fade.
Adding more tint to the coating than is recommended.
Interior coatings may also fade if they are near windows and there is significant sunlight exposure.
If the substrate is in good condition except for fading, clean as needed and repaint using a paint that is fade-resistant.