My last day?

"For the past 33 years, I have looked in the mirror every morning and asked myself: 'If today were the last day of my life, would I want to do what I am about to do today?' And whenever the answer has been 'No' for too many days in a row, I know I need to change something."
- Steve Jobs

It's an old philosophy, zen buddhist perhaps. And I do agree with it on some level.
But I wonder if it applies to all lives and situations. Many tasks worth doing takes a lot longer than 24 hours.  Say you just started a five-year education. And now you know you have only 24 hours left to live. Why go sit in stuffy classrooms that day, why not invite a nice girl or guy out for icecream and dancing? And yet surely that doesn't mean that it's not worthwhile to take an education?
Or say you'd be spending the day packing and preparing for a long travel the day after. Well, you're not going on the trip now, why spend the day packing?