A useful life and a visible life are not the same thing.

Visibility is a function of platform and circumstance. Usefulness is a function of whether something you did left a situation better. These come apart constantly, and confusing them means chasing the wrong one, since only one of them survives contact with reality.

Ask about a recent effort whether it was seen or whether it worked. If you find yourself optimizing for the first, notice what that costs the second. Most of the genuinely useful work in the world is not observed.