very weird thing, 1 window on a custys house wont stay clean, shes not complaining as such, just curious why it is just this 1 window, i have even spent more time on it, when it is dry it is crystal clear no spotting, but every 2 weeks when i go back, it is covered in dirt, and the rest of the windows are still spotless, as we don't use soaps i am baffled why it is not stopping the dirt blowing onto it, sticking, anyway i decided to trad this one, and surprisingly it is staying clean, her back kitchen window is facing a farmers field, i wonder if there is something in the dust that makes it stick to the glass. do any of you get this problem on some windows