In Germany, we used to have a VK-like social network aimed exclusively at university students that was big before Facebook even appeared. To this day I have no idea how that died so fast and hard, and how Facebook managed to overtake it when it hadn't even translated the interface. Ze English izn't zecond nature to all ze Germans.

Ah yes, the * VZs. From my perspective, there's a few reasons. One, my friends were very privacy conscious and would often either not sign up or use a weird name (like some people do). This made it hard to find people. Two, the user experience sucked hard. Third, they had different domains for different subgroups (I remember one for school children and one for students).

Finally, if you went travelling to any other country (except Austria or Switzerland maybe), the rest of the world had Facebook. So to keep in touch, you also needed Facebook, which had a better user experience. Why bother with both?

It's a testament to the poor state of the art in user experience for early social networking sites that Facebook had a (relatively) "good" user experience. It has always been horrible, except relative to most of its competitors.

So, not luck. Despite all the down votes