What is the 'it'?

I found the following in an obituary published anonymously (but, we now know, penned by William Shawn) in the New Yorker magazine, in the issue dated 8 January 1966. (Don’t ask.)

“The work of a good editor, like the work of a good teacher, does not reveal itself directly; it is reflected in the accomplishments of others.”

Two things.

One: I think this is a perfect encapsulation of the proofing mindset. Our sole purpose is to make the judge look good.

Two: see that semicolon up there? It ticks all the boxes.

Happy New Year!