I love the story of how Google Map came to be. Google wanted to build a local search to compete with Yahoo Yellowpages. But the aha moment came when the designers and product manager were playing with overlaying local search results on top of a Windows mapping app called Expedition. (I wonder how many good products were buried in big bureaucratic companies . Well, that's a different topic.) When you give people an unfamiliar but immersive and interactive experience, they explore without the burden of old behaviors and habits. The map interface encouraged the kind of exploration that the stagnant, incumbent competitor trained users not to attempt. I think the take home lesson is that you have to build a lens to allow users to see a new world rather than features to help them see an old world better.