Rockers are an essential for the off-road enthusiast and Jeeper. While your fenders, bumpers, gas tank, and skid plate all take hits while off-roading, it is the sides of your Jeep that are in the most danger. On light trails, dips, pot holes and sudden changes in elevation can max out the clearance on your Jeep. When you have one wheel going into or coming out of a particularly deep hole, your rockers will take the first hit.
On moderate and tougher trials where larger tires are a must, and you find yourself transitioning over objects, the rockers and skid plate are going to get hit. All of the areas where you can really show off the great flex on your Jeep will put the sides of your tub in danger of getting bent, scraped, and caught on the obstacle.