This is an extract from a forthcoming book. I like the fire escape analogy…:
[…] We can draw instruction from the past to see how these three scenarios, especially the last two, might work out. For instance, the original fire escapes in New York were frequently bolted to the outside of buildings. As a result, they often increased cost and harm to the occupants overall, according to an Atlantic article titled “How the Fire Escape Became an Ornament.” Today, they’re built into buildings, often the first thing constructed, and residents have never been safer from fires. Much the same as fire escapes in buildings, security built into IoT devices can bring new capabilities not possible in bolted-on approaches, such as updatability, hardening, threat modeling, and component isolation — all of which you’ll read about in this book.