I very much disagree with this approach. There are ways of gathering data without having to create a new social network for people to join. Asking people to join yet another network isn’t the answer.
You can leverage networks like Facebook to gather data on your users and build your CRM database. You don’t need your own social network to do that.
And yes, Facebook may go away one day whereas technically a brand’s social network could live forever. But if no one is going to your branded social network, what does it matter?
Seek out your customers in the places they are comfortable and find unique ways to engage with them. Don’t try to force your objectives on them, it won’t work.
I’m surprised people are still saying that you need your own social network but its possible I may be in the minority here.