Some reflections on the arduous nature of the writing process:
On plenty of days the writer can write three or four pages, and on plenty of other days he concludes he must throw them away.
Even when passages seemed to come easily, as though I were copying from a folio held open by smiling angels, the manuscript revealed the usual signs of struggle – bloodstains, teethmarks, gashes, and burns.
(from Annie Dillard, The Writing Life)
In my experience, smiling angels are a rare occurrence; the bloodstains etc. I can relate to only too well.