Here is a visual. Yellow lines represent where the wiper should move. For some reason mine is moving in the red.

 

Mine always go up to where it should but sometimes it doesnt always drop back down all the way to the bottom. Especially when the window is no totally wet. Prob just the wiper motors are a little wore out. I can always get min to go back down to the bottom if you spray the washer fluid and put the wipers on full blast. Just needs a little enforcement. Also check to make sure everything is tight.