Subscriptions
LTV (customer lifetime value)
LTV is the total contribution a customer is expected to generate over their whole relationship with a brand, best measured net of goods and fulfilment rather than gross.
Gross-revenue LTV is the common version and the misleading one, because it flatters subscriptions with thin margins. Contribution-margin LTV is what can actually be compared against acquisition cost.
It should be segmented by acquisition channel and by customer type. Subscription customers and one-time buyers have structurally different curves, and so do customers acquired through paid social versus email — blending them produces a number that justifies no specific decision.