There are plenty of reasons behind damage to a one-piece garage door. Most commonly, as a result of an intense impact. If for whatever reason you hit your door with your vehicle, you might end up affecting the hinge system that moves the door. These impacts shake the whole door, which can easily cause it to go off its track. If you notice your garage door was left hanging from its cables after an impact, you might be dealing with this kind of issue. Not all cases stem from a specific event. Sometimes, wear and tear can lead to all parts of the hinge system, which transfers the full weight of the door to rest on one side. A similar thing could happen if the bolds holding up the hinge get loose and alter the door mechanism.