Earlier quoted context omitted.
Decent iterations cannot be done without immediate management playing defense, period. As long as anyone is allowed to interrupt the iteration, then iterations are just going through the motions and won't solve any actual problems - because the problem is a lack of control. The engineer's response to unplanned work should be "Go talk to my manager", and the manager's response must be "Wait til next iteration". If the…
I've never know immediate management to understand the business nor the system as well as the ones with boots on the ground. I've yet to see a situation where the manager doesn't end up coming out of his office and asking someone on the team "so, what's this mean?"
I often use a bread-baking analogy here. Making software is like baking bread. This iteration, we get some flour, water, yeast, and salt, mix them together, knead, rise, and bake. And if someone comes in five minutes before baking is done and says "Can't you just add some raisins now? It's just a handful of raisins, it's not much work". No. It means starting over.