WhatsApp

In 2009, Brian Acton and Jan Koum had both just been rejected for jobs at Facebook. Neither took it personally enough to quit trying to build something — instead, they built WhatsApp, a messaging app with almost defiantly simple ambitions: send a message, have it arrive, reliably, without ads, games, or notifications trying to pull you back into an app you didn't need.

That restraint became the entire product strategy. While competitors added stickers, status updates, games, and advertising to drive engagement metrics, WhatsApp's founders resisted almost all of it. Koum kept a note taped to his desk reminding himself and his team: "No Ads! No Games! No Gimmicks!" The team stayed small on purpose — by 2014, WhatsApp was reportedly running on roughly 50 employees, with a strikingly small engineering team supporting hundreds of millions of users, because the product simply didn't require the complexity most apps accumulate to justify larger teams.

By February 2014, WhatsApp had grown to around 450 million monthly active users worldwide — larger than Twitter, growing faster than almost anything in tech — built almost entirely on word of mouth, in markets across the world, without a single major advertising campaign. Facebook, the company that had turned both founders down years earlier, acquired WhatsApp for approximately $19 billion, one of the largest acquisitions in tech history, for a company with a fraction of the headcount of its peers.

WhatsApp's story isn't really about being acquired for billions. It's about what happens when a product says no to almost everything that isn't the core problem. Every unnecessary feature is a decision to solve fewer things extremely well, or more things adequately. WhatsApp chose fewer, and did them well enough that fifty-some people built something worth more than companies fifty times their size.