Why does the screen rotate instead of the spray?
By maintaining a constant direction for the spray, a fairly strong current away from the strainer is created. Debris blown off the screen is moved a sufficient distance (20 to 30 feet in many cases) to prevent being reattracted to the strainer. A rotating spray, while able to blow off the screen, is too short in duration to move the debris far enough from the strainer to avoid being reattracted and therefore requires a natural current to assist in cleaning.
