When I buy a vehicle, it gets paint correction first. Waxes of any kind need a clean, even surface to ensure adhesion. Even after a thorough washing, you should see buffing pad when I get done with paint correction. It's brown. After correction, I lay down a coat of something, usually, Meguiars Ultimate paste. From there, every wash includes a maintenance coat of spray sealer, applied during the drying process. Right now I'm using Beadmaker, and my cars never stop beading water. I don't use sprays as the last line of defense, because they're not built to last. I use them to enhance the durability of the initial coat of wax.