There's a reason why most professional athletes don't play past forty. There's a reason why most military people don't stay in past their forties. The same can be said for people in labor intensive careers. But every so often you see that old timer still hanging in there. They seem to be just as physically capable as the rest, too. What separates them from the rest is experience. They've seen and done it all. They have accumulated knowledge--sometimes by learning things the hard way. They're survivors in a world of high attrition. That's what makes them so scary. That's what makes them so deadly. An old man who is still hanging in there when everyone else has either quit or died is not someone you want to mess with. They don't quit. They've played a real life version of king of the hill and won. Beware the old man in a world where men often die young.