Just had a talk with a customer that was not satisfied with my previous clean. She didn't say anything back then and just paid (even though I specifically told her to tell me if it didn't dry properly). But it turned out there were still drops of water on the window which did disappear. I of course offered them a discount now. I did it with 0 PPM RO only water with my DIY brush. It was a first clean so they were very dirty. So, anyone else had issue with this? I'm getting a bit worried as the some types of windows I encounter does leave different beading of the droplets. This could be why some customers doesn't call back, which of course is bad for reputation and business.