You do sometimes run out of things to say about writing. You do sometimes run out of things to write. What do you do then? You write about having nothing to write until something occurs to you.
Turning up to do the hard work and working hard is half the battle. If you never finished a book you probably never started one, or you forgot that you have to keep going until its done.
Books don’t form out of thin air, neither does writing. Anything of any worth forms purely out of effort. Effort is shaped by thinking big. I try to engage in both as much as possible.