Ive been using fairy latlely, dont thoink thats the cause , I would have liked to hear off a WFP guy on this .
Ive not had a problem with a customer in over 3 years , but today on the problem house the lady did politely ask me if I had forgottten to clean the windows , I had just done a full inside ans out the front out of the sun ...perfect sinnyside ...rubbish all smeary and very very fine dust glinting in the sunlight.
I was thinking it was from my microfiber ?, detailed outside but wiped all over inside , going over again made littlew difference, just altered the smearing / dust apearance.
Spose i could have tried just squeegying off inside and out ? maybe next time