That's a good example of a qualitative statement that would be a lot more credible with a lot of empirical evidence backing that up. "Experience shows" is not e

That's a good example of a qualitative statement that would be a lot more credible with a lot of empirical evidence backing that up. "Experience shows" is not enough here. Raises more questions than that it solves anything here really. Basically uncertainty is the key concept here. And cost, complexity, and time estimates are ways to get a grip on such uncertainty. Unlike software engineers, economists and sociologists are used to reasoning about and modeling uncertain situations. Going all hand wavy and winging it is typically not what they advertise.