Your model will usually be incorrect because in all but the most trivial applications the model will be the result of experimentation. Even if you “accurately”[

Your model will usually be incorrect because in all but the most trivial applications the model will be the result of experimentation. Even if you “accurately”[1] model the business rules, those rules themselves are subject to change as the business revives it’s model of the market, or customer relationship, or regulatory environment, or whatever. The main selling point of extreme late-binding (e.g. ad-hoc polymorphism, dependency injections, message passing, etc) is that lets you quickly revise your model. [1] Whatever that means.