Subscription fees. If a user is not willing to pay a nominal fee to use a service, that's an indicator that they are not drawing sufficient value from it. I would argue that most, if not all social media currently adds negative value to most people's lives - hence why they would stop using it if it were not free. The negative value stems from the fact that current social media business models are structured to service the interests of their advertisers (the true customers) above the interests of the users.