>A lot of technically sound solutions in this space simply lack the addictive quality to draw in the crowds. Instagram and similarly popular networks, for all their flaws, are designed from the ground up to exploit human nature. If you sit on any form of public transport, you can see this in action. People obsessively checking whatever networks they are on.

I think the main reason why they're hard to beat is the first mover advantage of becoming the first popular networks of their kind.

This advantage creates multi-sided markets. There are strong incentives for businesses to build on top of those platforms enabled by reaching a critical mass of users, this advantage is converting networks into a self promotional flywheels pulling in more and more users.

It gets addictive because businesses usually know their audience and journey they're on and create content incentivizing them to take the next step in that journey.

Of course it's addicitve for users if you can anticipate their next step, and for businesses if they have all those micro targeting options just a click away. The easy way wins.