Instagram Reels Ad Format Experiment: Success, Advertiser and Guardrail Metrics

You are the product manager for Instagram Reels, and the team wants to experiment with new ad formats. Which metrics would you track to judge whether a new format is working? ```hint Count every side of the market An ad in Reels affects more than Meta's revenue line. Ask who else gains or loses when the format changes, and make sure each of them has a metric. ``` ### Clarifying Questions - Which formats are being tested (for example, longer video ads, interactive or shoppable ads, or ads placed inside creators' reels), or should I propose them? - Is the main goal more ad revenue, better results for advertisers, or monetizing Reels without slowing growth in viewing time? - Will the test keep ad load fixed, so that we compare formats rather than more ads against fewer? - Which advertiser objectives matter most: brand awareness, website traffic, app installs or purchases? ### What a Strong Answer Covers - A stated goal for the test and a hypothesis for why a new format should beat the current one - A primary success metric that ties revenue to value for advertisers - Viewer experience guardrails covering engagement, retention and negative feedback - Effects on creators and on the rest of Instagram - An experiment design and launch rule that account for ad load, novelty and the shared ad auction ### Follow-up Questions - Revenue per user rises in the treatment group, but Reels watch time falls slightly. How do you decide whether to launch? - Treatment and control ads compete for the same advertiser budgets. How could that bias your result, and how would you fix it? - How would you detect long-term harm, such as viewers gradually learning to scroll past ads, that a short test would miss?