Earlier quoted context omitted.
There was nothing brilliant about buying two obviously successful apps: Instagram and WhatsApp.
I’m not here to defend Zuck, but those acquisitions only look obvious in hindsight. People thought Facebook was insane for paying a billion for a photo sharing app with a tiny team. And while WhatsApp was ubiquitous, it was very under the radar in the US until Facebook paid what seemed like an ungodly sum ($12bn) at the time. Instagram may go down in history as one of the greatest acquisitions of all time.
It didn't seem surprising at all at the time that Facebook bought both services, many people I knew were using them as much or more for social media than Facebook. Now, the values of course were a bit gawking but I'm sure experts crawled over a lot of their own internal figures and what they would expect out of both services. If any organization had enough social media data to evaluate these services marketability, it was FB.