Churn is the most important factor in the ultimate success of any subscription business. Investors and acquirers use churn to judge what a business is worth. CEOs know churn is the key to profitability.
But, above all, churn matters because the business can't grow when too many customers leave. It's that simple.
You can spend time breaking down how it costs more to acquire a new customer than to keep and expand an existing customer. And that's true. But it really misses the point.
Nobody wants to have anything to do with a business that isn't growing. Period.
And churn stops companies from being able to grow.