It's not easy writing a book.
I mean, it's easier than mining coal. It's easier than most factory work. It's probably easier than a lot of office jobs as well.
But STARTING to write a book... those first few inches you have to push that boulder till it hits the edge and starts to roll downhill... THAT'S the hard part.
Not as hard as teaching, granted. Or working on a farm. Or being a doctor or a nurse or a cop or a fireman. I doubt it's as hard as construction, either, or carpentry, or plumbing, or engineering.