While it is not strictly necessary to wax a car after washing it, it is a good idea to do so to protect the paint and maintain the appearance of the vehicle over time.
When your
car wash, you remove dirt and debris that can scratch the paint and cause damage. However, washing alone does not provide long-term protection for the paint. Waxing your car after washing it helps to protect the paint from the elements, such as sun, rain, and environmental pollutants, which can cause fading, staining, and oxidation.
Waxing also creates a smooth surface on the paint that helps to repel water and makes it easier to clean the car the next time. In addition, waxing can enhance the shine and depth of the paint, making your car look newer and more attractive.