Imagine an essay manuscript: Version A. Monday morning, I read through Version A. I'm not satisfied. Monday, Tuesday, Wednesday, I revise and revise -- cutting some ideas, adding others, tweaking the phrasing, trying to perfect the manuscript. Wednesday night I have the new version, Version B. My labor is complete. I set it aside.
Three weeks later, I re-read the manuscript -- Version B, of course. It lacks something. The ideas I had made more complex seem now too complex. They lack vigor. Conversely, what I had simplified for Version B now seems flat and cartoonish. The new sentences are clumsy, the old ones better. My first instincts had been right, my second thoughts poor. I change everything back to the way it was, one piece at a time, thoughtfully. Now I have Version C -- word-for-word identical with Version A.
To your eyes, Version A and Version C look the same, but I know them to be vastly different. What was simplistic in Version A is now, in Version C, elegantly simple. What I overlooked in Version A, Version C instead subtly finesses. What was rough prose in Version A is now artfully casual. Every sentence of Version C is deeper and more powerful than in Version A. A journal would rightly reject Version A but rightly accept Version C.