Growth loop anatomy: input, action, output, reinvest
A funnel ends. A loop feeds its best outputs back in as the next input.
Definition (near verbatim): a continuous system of value creation for a user during their lifecycle on the product; value may be retention, revenue or referral, not tied to one stage. Input = a new or returning user produced by earlier actions. Action = the actions that generate the desired outcome (several at once, not strictly stepwise). Output = results that lead to repeat behaviour and are reinvested to improve the next input. Loops are closed systems; the funnel is unidirectional and user value tapers after retention, revenue or referral.
The second framework of the course, and the one that turns growth into a system.