I wonder why the goal is “5x monthly income” and not “5x monthly expenses.”

No, it didn’t. My initial guess is that many of us would underestimate our monthly expenses—which often vary wildly from month to month anyway—or estimate only the barest-bones expenses and skip all of the extra stuff like restaurants/vacations/gifts/clothes/treats that we really do buy and should be factored into our spending.

But I don’t know. I am sending a request to Tom Anderson to ask if he wants to do a Q&A!