You've obviously never seen Les Stroud, the Survivorman.
That dumbass could easily put himself down for the dirtnap long before any of his support staff could get to him.
I like to think of him as playing russian roulette wuth a leatherman ;o)
Of course as I stated....yet he KNOWS it will be over in less than 7 days. Even in the arctic shows he had a rifle due his position on the critter food chain.
I can sit under a tree , drink from puddles an live under a debris hut for 7 days if I KNOW my ride out will be there at 0700 local
.
The fear an unknown factors are not present. Thus the missing part one must overcome that proves one ......tough.