Planning involves making assumptions, but it is important to constantly monitor one's assumptions and to be prepared for a "shortfall". This tip is related to an old proverb that is easy to forget in planning situations: "Don't count your chickens before they are hatched". The Japanese equivalent is "Toranu tanuki no kawazan'you" meaning one should be careful in planning something based on the assumption that you will possess yet unobtained things. The Japanese proverb is translated literally as "counting the skins of uncaught raccoon dogs". So catch, then count!

from http://encyclopedia.thefreedictionary.com/Japanese%20proverbs