One detail that stuck out at me is that after Thomas makes the claim that the single metric that matters in software is how easy it is to change, he moves on to show a balancing robot.
Now he doesn't directly connect those concepts, instead he talks about the PID algorithm. But what struck me is that Moshe Feldenkrais defined good posture almost exactly in the same way that Thomas defines good software, although he is talking about humans rather than robots. Specifically, Feldenkrais says that good posture in a given context is that which makes it easiest to move into the next desired position (or a spectrum of potentially desirable next positions).
"the claim that the single metric that matters in software is how easy it is to change"
Not if you have actual business people that you work for, then you're delivery ratio (things achieved per person/unit of time) is key. Because that delivers predictability and enabled planning. It lets you have discussions about what level of quality to deliver, staffing requirements, manage delivery expectations and plan releases.
The key thing is that it demonstrates the cost of change to them, so after being burned they come to appreciate the benefits of building in flexibility, but it also affects how they interact with the business. Delivery, and the burnup/down it allows, is the way we as developers can train product owners to predict the risk in what is coming and use their expertise to reduce it.
I've seen far more time saved, and lost, due to the business learning to ask the right questions, and raise the right stories, than due to building flexible software to handle changes. No matter how flexible your software is the really huge changes always bring massive pain - and as developers we don't have the domain knowledge to necessary to identify those whereas business people can.
One detail that stuck out at me is that after Thomas makes the claim that the single metric that matters in software is how easy it is to change, he moves on to show a balancing robot.
Now he doesn't directly connect those concepts, instead he talks about the PID algorithm. But what struck me is that Moshe Feldenkrais defined good posture almost exactly in the same way that Thomas defines good software, although he is talking about humans rather than robots. Specifically, Feldenkrais says that good posture in a given context is that which makes it easiest to move into the next desired position (or a spectrum of potentially desirable next positions).