Acquisition is expensive; Retention is free.
1The Three Types of Churn
Voluntary Churn (they chose to leave), Involuntary Churn (payment failure), and Happy Churn (they solved their problem and don't need you anymore). You must tackle each differently.
2Cohort Analysis
Don't look at average retention. Look at cohorts. If your latest cohorts have better retention than your old ones, your product improvements are working.
3Resurrecting Users
It's 5x cheaper to keep an existing user than to find a new one. Use win-back campaigns and feature announcements to bring 'dormant' users back into the active pool.
