Paint correction is a precision process that removes a controlled, thin layer of clear coat in order to eliminate the swirl marks, micro-scratches, oxidation, and haze that live in that top layer. Removing that layer restores a flat, reflective surface and recovers the paint's original depth and gloss.
It is not polishing in the consumer sense. It uses machine-driven cutting compounds and correction pads at specific speeds and pressures to achieve a documented improvement in surface clarity. The result is a finish that looks deeper and more saturated than the original. This is not because anything was added, but because the layer of defects was removed.
Done correctly, with measurement first and appropriate abrasive selection, paint correction produces a result that nothing else in the detailing market can match. Done without measurement, with too aggressive a compound, or for too many passes, it removes more clear coat than is safe and creates damage that cannot be undone without a respray.