You can add past titans Xerox and Kodak and IBM to the list who spent money every which way and in the end walked away from most of it. The ad money-making machine is slowly coming to an end, particularly the part where they get to be dominant over large portions of the Internet, the EU, China, the USA, and other countries are finally waking up to the scourge of social media and are starting to slice it up.
And it is the reason why he (Zuckerberg) looking for anything outside of social media.