I disagree. If everyone knows that an area is an amazing opportunity, then it's probably not an amazing opportunity. Every single runaway success at some poin

I disagree. If everyone knows that an area is an amazing opportunity, then it's probably not an amazing opportunity. Every single runaway success at some point had a whole host of people saying, "That's ridiculous-- it'll never work" on some level. examples: 1) When google was on its way up, it was a well-understood fact that no one could make real money on search. Oops. 2) When Excite was getting funding, everyone told them that search was dumb. People would do 1 search and bookmark what they cared about (and would never search again). 3) The very idea of youtube (giving away tremendous piles of storage and bandwidth) didn't seem very smart to a lot of people. Plenty of online video startups had failed. 4) Blogger couldn't get more funding and had to lay off their entire team. 5) If I described twitter to you 3 years ago, would you have been blown away by the idea? 6) Salesforce.com was not exactly warmly embraced by the enterprise when they first launched. 7) Marc Andreessen said he was constantly stonewalled by businesses when selling them stuff at Netscape. "The Internet? Inside our network?! MADNESS!" Hindsight make these ideas seem obvious-- but at the time, they were pretty ridiculous. As you say, most ridiculous ideas ARE really ridiculous. Thus the "necessary but not sufficient" part.