Most of todays drop aways are very good. There are a couple, like the Ripcord and the QAD, which I have not used yet, that do have a bit more going on inside that may fail. But for most of them, that come up when you draw and let down when you shoot, they are really rather simple. Any fixed prong rest has a spring to hold the prongs up. The spring is simply reversed on a drop away. They have cords to pull them up, and I suppose they can and have failed. But if connected properly, the chances of failure are very slim.