[SloopJon]

> The thesis is predicated on the idea that people claim this is the result of some study. I’ve never once heard it presented that way. It's a rule of thumb.

Code Complete cites eight sources to support the claim that the average cost to fix a defect introduced during requirements is 10-100x if it's not detected until after release. My qualm with Hillel's original assertion is that "They all use this chart from the 'IBM Systems Sciences Institute'" (emphasis added). I haven't personally vetted Steve McConnell's citations, but I am skeptical that they all share this common origin.

[jdlshore]

Laurent Bossavit’s The Leorechauns of Software Engineering looks into this claim (and several others) and finds that, yes, many of these studies do share a common origin, and often misquote/misrepresent it.