The passage that Tony cites deals with what "programmer productivity" means. It was taken from a paper presented at APL 99 from the author of the Zark Library of Utility Functions. With a search term like that, google returns a very focused result set.
“You know what, Russian is unreadable, I don’t know Russian, so it’s unreadable. If you don’t know it, it’s unreadable.”
Because APL is unreadable, it’s a write-only language, hence is unmaintainable.
“If we did not re-invent the wheel this would be a Cobol conference, we would have leeches all over our bodies, we would be using 8-track tapes.”
You should always be re-examining the wheel.
The full summary is quite inciteful. Especially the discussion about The Bergquist Equation of Productivity.