It's still touched by hand with dirty wash rags. Yes, they make an attempt to clean them as they use them but, it is a really weak effort. There will be lots of grit in those rags. There are some newer high tech places that use soft pad like rollers that are constantly washed during the process. Then comes the drying. Same towels used over and over. Then they even use widow cleaner and use the same towels on that. Several places I have seen use those red shop towels you can get in bulk at the auto parts store. Not to great on the paint. I saw one spray the window cleaner on the paint to touch it up. Real nice! Do it yourself, or expect to get more swirls.