
Shawn's right, at least if you're really into detailing your own cars or you do this for business.
Microfiber polishing cloths are superior at removing liquids of all types off smooth surfaces. They also can be very grabby or tacky. For example have you ever had a dried leaf break up and crumble on a microfiber polishing cloth? The small pieces of dried leaf can embed and intertwine into the nap of the microfiber and be very difficult to wash out and even pick out with your fingers. If you can't get the dried leaf out of the nap it would make that particular microfiber scratchy to use on paint.
Make sense?
Now lets use that above example with your wheel. If you have disc brakes, each time you step on the brakes small particles come off the brake pads and the steel discs and build-up on your wheels, we call this brake dust.
If you wipe your wheels clean with any kind of spray detailer and a wash mitt or microfiber towel, where do you think the brake dust, (abrasive particles), go?
They transfer onto and into your microfiber. Will washing remove 100% of all the metallic particles and brake pad particles? I don't know, but small things with jagged edges seem to embed into the nap of microfiber polishing cloths and are difficult to remove.
For this reason you might not want to use microfibers you use to wipe wheels clean on perfectly polished paint the next time you wash and wax the car.
So it's almost as though you need to have dedicated microfiber towels and polishing cloths separated by how and where they're used.
This all depends upon how deep you want to go, or how D.O. you want to get.
(Hope I just didn't complicate things for everyone)
A few years ago a friend of mine, Richard Lin, captured some pretty amazing photographs of metal particles embedded into microfiber polishing cloths, I don't remember where he was using the microfiber cloth but it was pretty scary to think about wiping down a nice paint finish with a microfiber with metallic particles embedded into it.