Choose a North-Star Metric and Guardrails for Messenger's Group Video Rooms

Messenger Rooms is the group video-calling feature inside Messenger: people gather in a shared room for a live video call. You own the feature and are asked how you would measure whether it is succeeding. Explain what success means for Rooms, which metrics you would track, and which single metric you would lean on most. ```hint Follow the room's life Trace what has to happen between someone creating a room and a group actually talking, and ask where along that path the user gets value. ``` ### Clarifying Questions - Is the main aim of Rooms to win group video usage away from rival meeting tools, to deepen engagement with Messenger, or to bring in people who do not have an account? - Are we judging a recent launch or a mature feature, and over what period should success be measured? - Which entry points count as Rooms usage: rooms started from Messenger only, or also from the company's other apps? - Can guests join a room through a link without signing in, and should their experience count toward success? ### What a Strong Answer Covers - A stated goal for Rooms and the user value behind it, before any metric is named. - A funnel from room creation through invites, joins and a real multi-person call, with a metric at each step. - One clearly justified north-star metric plus a small set of supporting metrics. - Guardrails covering call quality, safety and abuse in open-link rooms, and cannibalization of other calling features. - Segmentation (room size, use case, host versus guest) and how the numbers would be read over time. ### Follow-up Questions - Rooms created per day doubled, but the share of rooms where anyone besides the host joins fell. Is that good news? - How would you tell whether Rooms is growing total group calling or just moving calls away from existing group video chat in Messenger? - What would you measure to catch strangers dropping into rooms they were not invited to?