One aspect of the half-empty version is that if you don't feel you're good at something it can discourage you from even trying to push the limits.
I think I've noticed this a bit in myself - before I had broadband internet I was more willing to play around and tinker with things, now I struggle a bit harder to find motivation to try anything I'm not already good at.
But yes, the half-empty version is the depressing awareness that you're not really "good" at anything.