Everything that you have ever done in the past, you did in a present moment. Everything that you will ever do in the future, you will only be able to do in a present moment.
All your thoughts are thought in a present moment. All your feelings are felt in a present moment. And everything you actually say or do is said or done in a present moment.
Since you live your whole life in the present, moment by moment, it is wise to consider the wise thing to say and do in the present moment, in the here and now of that moment. It is also wise to prepare the wise thing to say or do in the future.
Someone who tends not to have zrizus (alacrity) might be thinking about how challenging it is to have zrizus. It's actually not difficult to have zrizus. Rather, it might appear difficult when you are not in a zrizus state, or when you are thinking about having future zrizus that you don't now have. But all moments of zrizus are just present moments, and when you are in that present moment of zrizus, it isn't difficult. Someone with a tendency to do things with zrizus will tend to look at zrizus as something he only needs to have one moment at a time.
([From Rabbi Zelig Pliskin''s book: "Taking Action" - pages 26-7] (Artscroll.com)