Mark Zuckerberg always knew.
In 2012, when Instagram was two years old, with 13 employees and no obvious path to profitability, Zuckerberg knew that the fast-growing photo app was a potential threat to Facebook Inc’s social media dominance. "Instagram can hurt us,” he wrote in an email. In an internal discussion about whether to buy Instagram – and other startups that might one day pose a threat to Facebook’s social media monopoly – he added: "The basic plan would be to buy these companies and leave their products running while over time incorporating the social dynamics they’ve invented into our core products.”