AARRR breaks the customer lifecycle into five measurable stages. Acquisition asks how users find you. Activation asks how many reach a meaningful first use. Retention measures whether they keep coming back. Referral measures whether they bring others. Revenue measures whether they pay.
The value of the framework is diagnostic. By measuring conversion at each stage, a team can spot whether growth is bottlenecked by a leaky funnel, weak activation, churn, or undermonetization, and prioritize accordingly. Many teams expand AARRR with awareness on the front and expansion on the back.