I wouldn't romanticize Orkut. It wasn't that great and I think Facebook would've steamrolled it all the same, much as it did numerous other regional social networks around the world.

I think the causality is that it was not great because Google did not care about improving it. So it got stuck in time and then Facebook kept improving. Even a strategy of copying Facebook’s innovations (like FB does in Instagram and WhatsApp) would an improvement.

Of course we will never know, but I think that betting on Orkut would have a better chance of facing Facebook than starting from scratch with Google+

It did steamroll some, but others are very much holding onto their users. VK is still way more popular than FB in Russia, for example.

For sure, I think directors simply didn't understand how online communities worked. Facebook must have been the first company to fully realise this, buying both Instagram and WhatsApp but not attempting to internalize their communities under the Facebook brand. It would've been pure capital destruction if they had done that.

I'm pretty sure they're going to have to write off the whatsapp investment. At least Instagram has a viable standalone business model. They'll lose the Whatsapp userbase at the drop of a hat, and it's already hard to monetize to begin with.

As someone who doesn't understand either, how do online communities work?

You build something addictive and "social".

Now how you sell user data is the Billion dollar question.

In the US, Reader had a huge social community. It wasn't just Orkut that had a large existing social community they could have leveraged instead of alienated, but the folks in charge of Google+ did not understand (presumably because they weren't RSS readers, presumably because they weren't from the communities where Orkut became popular).