Just as there are times to plant and to harvest, in accordance with the Sun's Cycles, there are times to rest and recharge as indicated by the Moon's Cycles.  

The Moon is called "Void-of-Course" during the period of time it last aspects another planet until it moves into the next Zodiac Sign.  This time period can last from a few minutes to a couple days.  

The essential meaning of this cycle is "nothing will come of it."  It is a time-out period.  It is not the time to invest your energy into any endeavor that you have an interest in receiving a result from because it will go nowhere.  Decisions and actions taken during these null and void periods result in nothing positive coming to fruition and/or unexpected difficulties arise.