You are interviewing for a product role at a travel-booking app. The interviewer asks you to pick one part of booking an Indian train ticket and make it meaningfully better. You may assume the app already offers search, booking and payment, and that seat inventory and waitlist rules are set by the railway, not by the app.
Choose a user and a moment in the journey, explain why it matters, propose an improvement, and state the trade-offs and the metric you would use.
100 points, 60% to pass.
The constraint matters: the app cannot create seats or change waitlist rules, so solutions that pretend otherwise miss the problem. The highest-anxiety moment is usually the waitlisted ticket — will it confirm, what is the backup. Strong answers pick a user (the family planning a festival trip, the frequent business traveller), focus on uncertainty (confirmation likelihood shown honestly, automatic alternatives, a clear refund path) and name the trade-off of predictions being wrong. Metric: completed trips on booked tickets, or rebooking rate after a failed waitlist — not searches.