"A bowl is meant to stay being a bowl, it’s not supposed to turn into a plate or a vase, or to become square, or bigger or smaller. While the target is static, the world is dynamic, which is what makes it break."
This is lucid analogy since many times in software, people think the target (goal) is static, or static enough.
Sometimes though, there might be pressure to make the bowl bigger, smaller, into a plate, a vase and attach a straw, all at the same time.