Does the root of this stem not from a belief that what we do is in some way bad, but a feeling that we're capable of so much more if only we could better channel our abilities?
We all have moments where we think "right now I'm doing amazing work" which make us look at all the other moments - our normal working level - as in some way insufficient.
In reality it's probably not realistic to work at that level continually, but that doesn't mean that we don't aspire to it so instead of thinking "I work at a decent level normally with moments of greatness", instead we think "I'm great but spend a lot of time being mediocre".
And maybe more than that it's very possible the moments when we think we're doing amazing work might not actually be our finest moments, just the "neatest" ones. There are days when I burn through things on my to do list but I suspect some of the days that really move things forward are far bittier and less immediately satisfying. I can spend a day being pulled from pillar to post by clients and think I got nothing done but the reality is that on those days I might have made a couple of clients happy and unblocked a couple of things that were delaying projects.
The TL;DR version: I suspect we're bad at judging what our real standard is, both in terms of when we're actually doing great work and how often it's possible to do it.
We all have moments where we think "right now I'm doing amazing work" which make us look at all the other moments - our normal working level - as in some way insufficient.
In reality it's probably not realistic to work at that level continually, but that doesn't mean that we don't aspire to it so instead of thinking "I work at a decent level normally with moments of greatness", instead we think "I'm great but spend a lot of time being mediocre".
And maybe more than that it's very possible the moments when we think we're doing amazing work might not actually be our finest moments, just the "neatest" ones. There are days when I burn through things on my to do list but I suspect some of the days that really move things forward are far bittier and less immediately satisfying. I can spend a day being pulled from pillar to post by clients and think I got nothing done but the reality is that on those days I might have made a couple of clients happy and unblocked a couple of things that were delaying projects.
The TL;DR version: I suspect we're bad at judging what our real standard is, both in terms of when we're actually doing great work and how often it's possible to do it.