Does the electrical service drip loop prevent a short to the grounding rod?

Drip loops prevent water from following the electrical service conductor into the service panel, causing shorts and other dangerous situations. So long as the low point in the cable is below the main lugs, water will collect and drip from there, and not continue to the exposed live parts of the panel. We usually have a drip loop in a place right next to the place the conductor penetrates into the head or the place where it "goes through" a wall or barrier. That way there is only a short "uphill" run between the drip loop and the penetration point for the conductor.