They risk falling into crevasses or over precipices, being buried by avalanches, swept away by a storm, suffering from hypothermia, frostbite and altitude sickness, or simply collapsing from exhaustion.
Those who take on the colossal mountains of the Himalayas must venture into what’s known as the ‘Zone of Death’ above 7,500 metres, where the body is incapable of acclimatising, and literally consumes itself until it dies.
And as the mountaineer Lionel Terray used to say, all this just to «conquer the useless».
And that’s if you actually make it to the summit, because the chances are you won’t. Climbing requires weeks of preparation including acclimatisation, multiple partial climbs to set up camps and work on the route, violent storms which prevent you from carrying out these tasks and multiply the risk of avalanches etc.
When the ideal conditions for attacking the summit finally arise, if they arise, you normally only have time and energy for one attempt.