Even if you keep your pickup truck in a garage out of the weather, that is no guarantee that your truck bed is going to remain free of things like rain, leaves and mud. That's because you drive it. Weather can happen while you're driving, or while you're parked in front of your buddy's house, or while you're at work. That's why truck tonneau covers are such a great thing. You may not think tonneau covers are a great thing until you try to keep your truck bed clean using only a garage or car port. Then you'll see.