That's not true. There are plenty of companies where referrals are non-essential or non-existent, but the company is able to turn $1 of advertising into an LTV of $20 even if the customer churns. Imagine an app that helps a woman through pregnancy, for example. The churn rate on its own doesn't mean that the product is necessarily trash and the lack of referral doesn't mean that the product isn't appreciated. Some buyers have needs on short timescales or do not naturally refer other buyers.