Actually, the family story is that Mallory spoke that famous line in exasperation. After a two hour lecture on the plans for the next expedition, a little old lady in the front of the room raised her hand and asked him, " So, why do you want to climb Everest, anyway?"
The most recent book about GM includes some of his speeches about climbing, and they are quite romantic in a Victorian way. It has a better answer for the question 'why'.
Do you suppose they will ask about us, why did we spend endless hours sitting in front of our computers?
Blessings,
Barbara