For me, that means pushing ahead into subjects you’re not familiar with and wresting with them until you can–shying away from the “easy read.” It means reading Feynman over Friedman, biographies over business books, and the classics over the contemporary.
Now we all borrow occasionally, and that’s okay if you fully understand the consequences and don’t make it a habit. I did that the other night. We pushed an update to our single-signon system for Basecamp, which had me working until 1:30 AM. That wouldn’t have been so bad if it wasn’t because I got woken up at 5 AM to help deal with an issue that arose. But the costs the following day were typical, numerable, and high: