I looked at my own to-do list today and thought, honestly, anyone could do this exactly as well as I do. Nothing on it needs me specifically. And if it doesn't matter that it's me sitting in this chair, I can't figure out why it should matter that I show up at all.
More people experience this than they realize.
You feel anyone could do your job, and it drains the meaning out of it.
If this sounds familiar, the Library can help you find the bigger picture.