The trick is that you can't just 'plan', 'implement', evaluate' or 'revise' at any one time.  They are so intertwined that there is always an overlap or connection.  You can't stop one or two or three to do any one.  They all need to be fed, and at the same time.  So balance becomes the operative word.  Usually planning does comes at the beginning of a day and evaluation at the day's end, but it doesn't always happen according to any schedule.  Anytime, any place is good for any of them.  A good plan never seems to not be revised before implementation, and evaluation is really a part of each of the other three.  For me they are only four words to help me describe for myself this huge, lifelong process we are all involved in.  I can just as easily use other words, say like, faith, hope, charity and love; or repentance and endure to the end (which I like to use the word 'continue' instead of 'endure') or even just one word:  faithfulness.  However you choose to describe your personal journey we all find ourselves in the same boat.  The better we understand 'it' the heavier it weighs upon us, or in other words: the more the we are given the more that is required of us.  So kids, if you think that your lot is hard now just wait until you age some and learn some more and are faced with that greater responsibility that comes with that territory.  And you'll have to face it without the 'strength of youth', but with the 'wisdom of age'!