Triaging a 404 Error Reported by Sales in the Booking.com App

You are a product manager at Booking.com. A sales manager tells you the app is showing a 404 error. How would you investigate? ```hint Scope before cause Before guessing why the page is missing, pin down exactly what the sales manager saw and how many people it affects. The answer decides how urgently the rest of the investigation has to move. ``` ### Clarifying Questions - Which app is affected: the traveler-facing app or website, or a tool that accommodation partners use to manage their listings? A report from sales may be relaying a partner's complaint. - Did the error appear on one specific page or link, or across the app, and on which platforms (iOS, Android, web)? - When did it start, and has anyone else, such as customer service, other sales staff or monitoring alerts, reported the same thing? - Do I have direct access to error logs, dashboards and the release history, or do I work through the engineering team? ### What a Strong Answer Covers - Gathering precise details from the reporter and reproducing the error - Sizing severity and the impact on users and bookings before deciding how fast to act - What a 404 means technically, and a structured set of plausible causes - Localizing the cause with logs, segmentation and the change history, and driving the fix with engineering - Communicating with the reporter and affected customers, and preventing a recurrence ### Follow-up Questions - The 404s turn out to come only from an older version of the mobile app. What do you do for users who have not updated? - The error hits pages for properties that were removed from the site. Is it a bug at all, and what would you change? - How would you set up monitoring so the team learns about a spike in 404 errors before sales does?