They traded their company for hundreds of millions of dollars. Good on them for turning a product into something that was so lucrative for FB and a real enjoyment for so many people the world over. I think it can't be understated how Instagram has become a pillar of so many brands and online businesses today.

But in reality their departure is really part of the business of software, the founders sell out, become exceedingly wealthy. After a few years the disillusionment with being part of a corporate machine (and not in control) sets in and they quit to spend time on their burning man floats. Its always been this way and theres nothing wrong with that.

I think many of us would do exactly the same given the option of struggling for a decade to profitability or a $10m+ exit with a comfortable VP level role.

I find it interesting that Instagram would want to include more adverts, as I find myself drawn to brands/interests without the help of annoying ads.