When you have a purpose, you have a framework that makes every decision clearer than it would otherwise be. Your purpose gives you criteria to measure against every decision before you. It also acts as an organization system to look for, gather, and evaluate evidence. In all things, you are able to evaluate the costs and benefits against your chosen purpose: either a clear best choice emerges, or you will have done the due diligence necessary to prove to yourself that the decision isn’t terribly important to you.