Why do I need a panel wipe before applying ceramic coating?

Polishes, glazes, waxes and some shampoos leave oils and fillers on the paint that can stop a coating from bonding properly and can also hide scratches that reappear later. A panel wipe, usually a solvent-based or diluted isopropyl alcohol prep product, removes these residues so the coating bonds to bare clear coat. Use clean towels, flip them often and follow the product's guidance, since some panel wipes are too strong for plastics or fresh paint.