I think he did state that the benefit is also much higher, but it was a bit subtle. He argues that the cost is higher than expected because you have to design t

I think he did state that the benefit is also much higher, but it was a bit subtle. He argues that the cost is higher than expected because you have to design the tests and design the system to be testable. He then states that this isn't wasted effort because, "Something that is hard to test is badly designed." And then hammers the point home with the pacemaker story and a bit of ranting. I agree with him. It took me a few years to realize that if code is hard to test, it is hard to debug. And if it is hard to debug, it is hard to reason about. And if it is hard to reason about, then it is likely to have hidden bugs.