Primary and secondary KPIs are the main metric you use to measure whether your business is on track. Retention and churn are going to actually contribute to your revenue growth. You need to make sure you're making money on each user, not giving away free money and calling it growth. Three to five secondary KPIs is reasonable.
YC Visiting Group Partner Divya Bhat talks about how to set your KPIs (key metrics) and how to prioritize your time. This talk helps founders launch faster and set goals in order to make real progress.
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