I'm probably going to jinx myself with this statement - but I've never had a trap system failure. I did once fail to get the ring engaged past the keeper on my harness and fall in because of that (come to think of it, I think Tad was on my boat at the time). Since then, I've cut all the keepers off my Harnesses. You have to stay after them with maintenance and be careful with the rigging. If you think "that might be a problem", fix it.