[d3vvnull]

Any achievement has scope and context. What one achieves in any activity may or may not transcend that activity. The meaningfulness of the activity itself may not carry beyond the individual or beyond a select group. So I think, ultimately that the achiever has to make the final judgement as whether achieving the goal really matters to the achiever and whether it matters that the achievement is important to others.

Also, treadmills are not entirely useless, even in the metaphorical sense. I may not visibly being going anywhere, but my mind may be active and going through a process of re-wiring and preparation for other challenges.