ABSTRACT
Millions of software engineers around the world build software according to the specifications provided to them by product management. For many years, this was an entirely fine way of building software. New product development could take years and new software releases for existing products would happen yearly or sometimes even less frequently. And even more important, the amount of competition was limited. Over the last decade, however, there has been a major shift in how software gets built. Very few companies can afford to invest R&D resources over calendar years before getting a return on the investment and consequently the time and resources available for new product development as well as product releases have been shortening and shrinking.
