Facebook's true north metric for platform growth is the number of members who connect with ten friends in seven days.(77) Just having a user sign up for an account is insufficient to inspire the engagement rates that Facebook needs to later monetize that user through advertising. Similarly, Slack focuses on teams that have exchanged at least 2,000 messages.(78) Once a team has reached this threshold of usage, they're much more likely to stick around and eventually upgrade to paid plans.
