You are a product growth analyst for a consumer installment payments product used across merchant checkout, a shopping marketplace, and a mobile app. Leadership wants a single North Star Metric to align product, engineering, and marketing, but teams are pushing different candidates: monthly active users grew from 6.2M to 7.1M in 6 months, checkout approval rate improved from 41% to 45%, and monthly transactions per active user fell from 2.8 to 2.4 over the same period. A recent expansion into lower-frequency categories like travel and home goods increased gross merchandise volume 18%, but repeat usage and 90-day retention were flat. The concern is that the wrong North Star could reward top-of-funnel growth while masking long-term customer and merchant value.
How would you determine whether a metric is a strong North Star Metric for this product, and how would you decide among competing candidates? What would you look for to ensure it reflects durable value creation rather than short-term volume gains?