How good are waxes sprayed on at car washes?
Because these waxes have to be diluted with water to be sprayed on your car, you are getting minimal protection. Not to mention, if it was durable, the wax would be visible on your windows. It is far better to apply wax by hand to insure maximum protection. Plus if you use a one-step cleaner/wax, it will also deep clean the paint and remove contamination and oxidation. These things cannot be removed from an automatic car wash.