Douglas Cartwhright:

The cut and dried version comes from paraphrasing the German philosopher Nietzchie (the one who supposedly said ‘God is dead’) : “A man can endure how if he has a strong enough WHY” [my italics]

This is a great guest post that looks at how your focus and drive on a  task can change given the reason for doing something. It is true that you will bear down and focus hard if your life depends on it, while it is terrible hard to do the same when you could care less whether you complete something you deem worthless.

via How to Improve Focus With the Power of Intention.