Zero-Based ThinkingBrian Tracy uses this concept in most of his books and seminars. To evaluate a situation one considers the following question.
Knowing what I now know, would I get into this business/job/situation again?
If the answer is yes, then continue your evaluation of the situation and make relevant changes.
But, if the answer is no, then the next step should be to get out of the situation as fast as possible, i.e. going back to zero; to before the situation started; to the topmost square of the snakes and ladders game and starting from scratch; start afresh.
More information about his books and seminars is available on his website : BrianTracy.com.