Paint correction stages, decoded: what the machine is actually doing
Paint correction is controlled abrasion. A machine polisher works a pad and an abrasive compound across the clearcoat, levelling the surface down to the depth of the deepest defect being removed. A swirl mark is a valley in the clearcoat; the machine removes the surrounding peaks until the surface is uniform again and light reflects cleanly. This is why correction is finite: each pass spends clearcoat you cannot get back, and why the depth-gauge readings from the walkaround matter so much.
A useful acceptance test at handover: ask to see the finished paint under the detailer's inspection lamp, not just in flattering daylight, and check the panel edges. Machine work concentrates heat and cut at edges and creases, so clean, un-burned edges are the signature of careful work. Holograms — faint buffer trails visible under direct light — mean the final refining pass was rushed.