Why does my car paint look dull even after washing?

Dull paint after a proper wash usually points to one of three things: bonded contamination such as road film or fallout, fine swirl marks that scatter light, or oxidation of the clear coat or single-stage paint. Decontaminate first and check the paint under strong light. If it is still dull, light polishing can remove swirls and mild oxidation and restore clarity. Paint that looks cloudy or chalky in patches may have failing clear coat, which polishing cannot fix.