Why do you have to understand the life cycle to understand projects?

If a project can be compared to the life cycle of a human, then humans need different things during their life. Very basically, as babies we need nurturing, as we grow we are educated, then we can get jobs and then we retire. During each of these cycles our inputs and outputs are different. from a project point of view, failure to understand this will mean you will either be using the wrong type of resources, stay in a cycle too long (i.e. expending both times and resources unnecessarily), don't have clean hand-overs (i.e. again wasting effort) between life cycles, or as a lot of projects tend to do just go on and on expending/wasting resources that could be far more usefully deployed on other projects. Having clear and well defined understanding of what cycle you are in, brings focus to a project in order to get you to the next phase or to the delivery point and ultimately the support and close out phase.