Its possible to get the windows and frames done properly on the first clean, it just takes more time.
The frames are very dirty on the top, and also if its upvc frames with vents, as the water will drip from them.. check it..and its brown, it only takes a few dirt particles to get streaks!
First scrub the top frames and the top 2 inches of the window up down, then side to side, back to up and down, do it for all the windows. Wait till they have semi dried, you can then see which ones haven;t fully be cleaned properly cos of the streaks. Again brush the top frames of the ones that have streaks.
Then you brush the windows up to the top of the windows minus the 2 inch that u have already done, then rinse it down missing the last top 2" of the window.. perfect results first time every time.
But it takes practise! Its not that it takes 2-3 cleans to get it right using wfp, its the fact it takes you personally 2-3 cleans. All you need is experience with it.