Sometimes when we want to study, we find it difficult to keep our focus on the topic at hand. But telling yourself, Just five minutes," will probably extend your focus for the next five minutes. You might then decide to study for "just (another) five minutes." These five-minute segments can be renewed as often as you choose.
There are many tasks that might need your attention, but you don't feel like doing them. However, you could find it relatively easy to take action for only five minutes. "Just five minutes" will enable you to do many things that you would otherwise neglect. Variations of this theme are: "Just ten minutes." "Just thirty minutes." "Just one hour."
(from Rabbi Zelig Pliskin's book: "Conversations With Yourself", p.142) [Artscroll.com])