Down is deadly, as most climbers know. Eighty percent of Everest fatalities have occurred during the descent. There are a few obvious reasons. Your balance is off and the footholds precarious, sloping away, unexpectedly fragile, primed for a slip. Worse, you face away from the mountain, forced to stare at the terrifying emptiness below.
Particularly debilitating is the energy crash. As adrenaline - more technically, the hormone epinephrine - wanes, fatigue and disorientation come crashing down like a wave set. Plenty of climbers have plunged to their deaths on Everest, but dozens of others have simply sat down and faded away.
I picked up this book originally because I was looking for a book on Everest that covered the commercial "expeditions" and development of the tourism on the mountain as well as the technical aspects of mountaineering, and most of all, a book that was not written by Jon Krakauer. This really is an excellent read so far.