Venkatesh Rao’s post on the complexity – and more – of contemporary supply chains is a fantastic read:
Many engineered artifacts can be viewed largely in terms of their designed function without much loss in understanding. If you’re designing a truss, material properties and stress/strain calculations tell you almost everything you need to know about how it will perform in the field. You can go from paper-napkin sketch to CAD design, to prototype, to production artifact, via a largely one-way flow, with very little iteration, and not go too wrong.
This is not true of supply chains. Even though many of the pieces are designed and put together the way other engineering artifacts are, the effects of those behaviors are different. And they evolve over time.