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In 1985, after Joe Simpson broke his leg descending Siula Grande in Peru, Simon Yates lowered him down the mountain in 300-foot rope stages until Simpson went over an ice cliff and hung free, unable to climb back up, while Yates was slowly being pulled off his own stance. After roughly an hour, with no way to see or hear his partner, Yates cut the rope, and Simpson fell into a crevasse.
A goal that small can actually be achieved, so each one produced momentum and kept overwhelming despair from settling in. It also turned an impossible whole into a chain of possible next steps.
While he was near-delirious, Simpson heard a calm, detached inner 'voice' issuing orders, like 'go on, keep moving, you're late.' It worked separately from his panicking, emotional self. This split let a cold executive function keep him acting correctly after hope and reasoned motivation had collapsed, which suggests survival can run on a stripped-down directive layer rather than on belief.
Yates cut the rope because the alternative was both men dying, and Simpson himself defended the decision, saying he would have done the same. The rightness of a decision made under forced, incomplete information does not settle how its maker has to live with it afterward.