The most important distinction needed for decision analysis is that between decision and outcome. I tell my students that if they learn nothing else about decision analysis from their studies, this distinction will have been worth the price of admission. A good outcome is a future state of the world that we prize relative to other possibilities. A good decision is an action we take that is logically consistent with the alternatives we perceive, the information we have, and the preferences we feel. In an uncertain world, good decisions can lead to bad outcomes, and vice versa. If you listen carefully to ordinary speech, you will see that this distinction is usually not observed. If a bad outcome follows an action, people say that they made a bad decision. Making the distinction allows us to separate action from consequence and hence improve the quality of action. http://web.stanford.edu/class/cee115/wiki/uploads/Main/Schedule/DAPracticeAndPromise.pdf https://hbr.org/2014/11/making-good-decisions