[Perfectlap]

Clay makes a big difference for waxing purposes. If you try to wax/top a dirty car, the end result will not be nearly as good. After claying (and washing again to be thorough) you should polish the paint. It fills swirls and gets at the remaining residues that simply pressing down on the paint from claying won't lift away. The surface will then be even and clean so that reflection from the light will not magnify either the swirls or stains.