We have a large window that we can't clean ourselves because of the location, so we bought the Winbot. It cleans quite well, but at the start and end points and around the edges it leaves traces that you have to clean again. And when the sun is shining, you can see the tracks the robot has made. So if you want 100% clean windows, you either have to do it yourself or hire a professional from time to time.

I don't quite understand the question. Generally, some dust or something remains in the place where it is finished, so I would wipe it again briefly with a cloth. Above all, you have to go back to the spot at the end of the cleaning anyway, because the robot has to be removed again.