Premature and/or excessive lightening of the paint colour, which often occurs on surfaces with sunny southern exposure. Fading/poor colour retention can also be a result of chalking of the coating.
Use of an interior grade of paint for an outdoor application.
Use of a lower quality paint, leading to rapid degradation (chalking) of the paint film.
Use of a paint colour that is particularly vulnerable to UV radiation (most notably certain bright reds, blues, and yellows).
Tinting a white paint not intended for tinting, or over-tinting a light or medium paint base.
When fading/poor colour retention is a result of chalking, it is necessary to remove as much of the chalk as possible (see Chalking). In repainting, be sure to use a quality exterior house paint in colours recommended for exterior use.