" It was a wake-up call to me to learn that Airbnb was by no means unique: Instagram started as a location-based social network called Burbn (which had an optional photo feature). It attracted a core group of users and more than $500,000 in funding. And yet the founders realized that its users were flocking to only one part of the app—the photos and filters. They had a meeting, which one of the founders recounts like this: “We sat down and said, ‘What are we going to work on next? How are we going to evolve this product into something millions of people will want to use? What is the one thing that makes this product unique and interesting?’”7 The service soon retooled to become Instagram as we know it: a mobile app for posting photos with filters. The result? One hundred thousand users within a week of relaunching. Within eighteen months, the founders sold Instagram to Facebook for $1 billion. I know that seems simple, that the marketing lesson from Instragram is that they made a product that was just awesome. But that’s good news for you—it means there’s no secret sauce, and the second your product gets to be that awesome, you can see similar results. Just look at Snapchat, which essentially followed the same playbook by innovating in the mobile photo app space, blew up with young people, and skyrocketed to a $3.5-billion-dollar valuation with next-to-no marketing. "
― Ryan Holiday , Growth Hacker Marketing: A Primer on the Future of PR, Marketing, and Advertising