From Frank Chimero's Other Halves:

Knowledge work has its name for a reason: the challenges naturally swing towards the cerebral, and doubly so if you work in design for digital products. You spend hours and hours considering ways to think about what is ultimately an immaterial thing. And who’s to know if it’s done or right?
Writing is a lot like that, too. So, on average, most of my waking hours are spent wrestling with ghosts.