Metrics question

You’re the PM for instagram feed and you see MAU went down 20%. Why did this go down?

Practice this question out loud. An AI interviewer asks it, follows up like a real interviewer would, and scores your answer. Type or speak.

What this question tests

Tests rapid, structured root-cause diagnosis of a large drop in a core usage metric under time pressure.

Verify the drop is real: check for a tracking, logging or reporting bug before investigating any product cause.
Check for a technical cause: a recent app release, an outage, or an API or login issue preventing users from accessing the feed.
Check for a competitive or behavioral shift: increased usage of Reels, TikTok, or another surface pulling users away from the main feed specifically.
Segment the drop by platform, region and age group, since a global technical issue would show broadly while a behavioral shift often concentrates in specific segments.
Cross-reference the exact drop timing against any recent releases, policy changes or known external events before proposing next steps.

Rules out an instrumentation bug first, the fastest and most common explanation for a sudden large drop.
Considers internal cannibalization, users shifting from Feed to Reels within Instagram itself, a real and specific hypothesis.
Uses segmentation to distinguish a global technical cause from a localized behavioral shift.

Jumping to a product fix before confirming this isn't a tracking or login bug.
Ignoring the possibility that users shifted to another surface within the same app, like Reels.

How would you tell if this is a login or access issue versus users actually leaving?
What immediate step would you take while root cause investigation is still ongoing?