The main source of frustration for creators is the inability to create what we envisioned.
The left circle is our expectations - what we want to create (e.g. an idea for an essay).
The right wonky circle is what we actually make in reality (e.g. actual essay you wrote).
This orange area is our frustration: Creator's frustration = What we envisioned - what we actually made
It's that feeling "hmm this is not as good as I wanted to make"
You can try to minimise this area by editing. But it's impossible to eliminate it completely.
So at some point, you just have to say "ok this is good enough", hit publish and move on to the next topic.
Like @moretothat says,
"The hands cannot re-create the idealized blueprints of the mind—no matter how hard we try. Perfectionists try to ignore this reality, but doing so will always result in a chase that never ends."
We should aim for 95% (good enough) rather than 100% (perfect) because "100% is a construct of the mind, and pursuing it will take you away from exploring other areas of interest"