Yesterday afternoon saw the second seminar of the day, 'Modeling Primer' by the IME group. This lecture delved into the world of rational decision making: making the right decision at the right time. The right decision takes experience, intuition and knowledge (facts and rules).
It is a myth that it is easy to find a solution to a complex problem, for simple cases the decision is correct but you are taking a chance for complex problems.
A model is an adequate (for a purpose) representation of a part of (interdisciplinary) knowledge. I reiterate a quote from the beginning of June: All models are wrong but some are useful. They provide a tool to HELP find the best decision. BEST is merely a suggestion of decisions for reaching certain goals which can be done through analysis of trade-offs between conflicting goals or an evaluation of the consequences of various decisions.
A model requires consistency, transparency, replicability and documentation. Something to remember is that RARE events do happen, the low probability mean it won't happen.
Some parting words of wisdom from A. Einstein - "Everything should be made as simple as possible, but not one bit simpler." Words to live by.