A few years ago the crew got a call to a nearby ex mine tailings area that's popular for motocross style riding. There's a quite steep hill maybe 100 yards (meters) long on one side. A fellow with a MX style bike was done his day's riding and he took off his gear at his pickup truck including his chest protector, and got ready to load his bike. Then he decided to go up the hill one more time.
He was going up the bike width hill trail when he came up to a previous rider who hadn't made it and this guy's bike was laid down. Our guy went around him partly in the bush so as not to lose his momentum, he figured to carry on around the downed guy and make it up the hill.
What he didn't see was a dead spike top that was pointing down the hill. It stabbed him, or rather he impaled himself on it, right through the heart. He was dead immediately.
You don't always see everything, and this can happen just as easily in a side by side.
Be aware.