Swirl Marks

They show in sunlight. Poor washing causes them. Polishing removes them. They are most visible on dark cars under direct sun or petrol station lights. Machine polishing with a suitable pad and compound removes a tiny layer of clear coat to level the surface. Afterwards, protecting the paint and using careful washing habits keeps them from returning. Each correction removes clear coat, so it should not be repeated too often.

Grit drags across paint.

Brush car washes cause many. Use soft drying towels.