Churn rate has a direct effect on Lifetime Value (LTV). If you can halve your churn rate, you will simultaneously double your Lifetime Value. It is an enormously important metric in the SaaS business model.
Churn can usually be attributed to low customer satisfaction -
among other possibilities,
which can be measured with surveys tools like Survey Monkey,
Survey.io, or
Net Promoter Score.
Renewals are also likely to contribute to churn rates, though in a different manner. Issues with the product (like a bad user interface or high learning curve) may contribute to a lower use of the product and consequently a higher churn rate.
Use the "Churn" sheet of the workbook to help calculate this.
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