Cleaned my windows today. Few streaks left. Cleaned and rinsed them thoroughly. Happened last time I cleaned them to. They are regular double glazed.
Makes me question whether the same is happening to my customers. Last time it happened on my windows it prompted me to take more time on customers windows and I now overclean to be honest.
Not great.
it could be technique or your water quality, but from what you say it doesn't sound likely in this instance
as others have said some windows just dont take well to WFP.
if we have a window where the streaking is causing a problem, and we have tried cleaning the hell out of it to little effect... missing the top seal usually solves the issue.
also remember you will be a lot more critical of your own work than a customer will.
we can get fixated on trying to get them 'perfect' when in fact 'good enough' is good enough
if you are advertising and charging for a service where everything will be perfect that's like a 'michelin star' restaurant, where you pay through the neck for it.
but plenty of people love McDonald too where you get good value, and a consistent standard of food served in clean restaurant etc... but few would say its the best burger they can imagine. it is good enough for lots of people. and people love them for it
for our customers the quality of the window clean is only part of what our service. the other parts are how reliable you are, how consistent you are, how friendly and professional you are, how easy it is to pay.. all these things are probably as important , or arguably more important than the clean itself