A lot of times they don't. The approaches to Everest are littered with the bodies of people who were not only not rescued, but not recovered post-mortem.
I also thought that the bodies of Everest climbers who die are often left right where they die. At 29,028 feet, there is so little air that helicopters can't fly, and so little oxygen that just entering the "Death Zone" (26,250 feet and up) is literally a death-defying experience even with tanked oxygen. It is often impossible to do even for a dying climber.
You are correct, I can't think of many times when we saved folks from Everest. All one has to do is look at the 1996 tragedy on Everest, some of the guys that died were U.S. citizens. Many people who climbed Everest in the months and days following their death saw their bodies. As a matter fact, sometimes the guys from Everest are saved by another country. As with the case of another Dallas resident who was left for death on Everest twice and survived.
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