I was watching the window cleaner this morning pull up and clean the neighbours across the road. Older guy who was continuously out of breath. He was using a Trolley system and started with the upstairs windows, he gave them a good scrub but never rinsed off at all. When he came to the downstairs windows, again he scrubbed well but never rinsed either but got his scrim out did some detailing instead. He spent a good minute wiping each window. Thought it was a bit weird to be honest.