The modern software development cycle, by contrast, moves in weeks, days and even hours—because software is a malleable digital item whose only limits are the human imagination.There's some profound truth there... but.
First, even an industry-leader like Amazon, which the authors put forward as a model, can only get so many lines of code written in a week.
Second, putting the issue of days and weeks aside, we need to be careful about the idea that software is "limited only by imagination".
A lot depends on what you mean by imagination. We can imagine a computer program that thinks just like a human. But we are in no position to write such a program.
We can imagine the program's user interface - perhaps we would like it to converse with us helpfully about our strategy in Afghanistan - but we can't really imagine how such a machine would work at a producible level of detail.
Implementing imagination, however inspired,
hangs on the question of whether
someone can cobble together
the actual pieces required.