“The best markets are usually the ones in which competition is fierce because the opportunity is big. How long should you stay lean before attacking?”Ben Horowitz in defense of the fat startup. Most companies solving high value problems can probably relate to this challenge. It’s one thing that Twitter can stay lean when it comes to getting P/M fit on one side of it’s business - starting to build an audience - but claiming that they have been lean in getting P/M fit when it comes to the money making side of the business is another thing… P/M fit for making money is harder. A lot harder. Specially when you solve problems people actually care about.