If You Usually Do Nothing, How Do You Know When You're On Vacation?

From: Tom Modica

Dear Tom & Ray,

I have recently read "Night Fall" by Nelson DeMille. In the book, the author poses a question which he doesn't answer. After thinking about it for several weeks, I realized one of you is an expert on this subject.

The question is: "If you do nothing, how do you know when you are finished?"

Your other brother,
Tom