I used to work with a guy who prided himself on his work ethic and productivity. He would pound away at the code daily yet, he was probably one of the worst programmers I've ever known. He was so interested in being productive (which is laudable) that he never took enough time to rest, recharge, and integrate what he had learned. He thought he was delivering quality results because his metric was wrong. Meanwhile, multiple people had to go behind him and rewrite his code because it was so bloated and inefficient.

The funny thing is, he told someone he thought I was the worst programmer he'd ever worked with because I didn't come in and grind out hundreds of lines of code each day. Maybe he was right but, I suspect he had that opinion of other people at the company that didn't meet his skewed standard.