" In climbing, having confidence in your partners is no small concern. One climber’s actions can affect the welfare of the entire team. The consequences of a poorly tied knot, a stumble, a dislodged rock, or some other careless deed are as likely to be felt by the perpetrator’s colleagues as the perpetrator. Hence it’s not surprising that climbers are typically wary of joining forces with those whose bona fides are unknown to them. But "

― Jon Krakauer , Into Thin Air: A Personal Account of the Mount Everest Disaster