Diagnose a Sudden 50% Weekly Drop in Paytm Payment Transactions
Company: Paytm
Role: Product Manager
Category: Analytics & Experimentation
Difficulty: medium
Interview Round: Other
Paytm, the Indian digital payments app, saw the number of transactions on its platform fall by 50% last week. What could explain a drop this large? Lay out the possible causes, the order in which you would investigate them, and the evidence that would confirm or rule out each one.
```hint Half the volume in one week
Payment habits rarely change this much in seven days on their own. Start with what could change abruptly: how the number is counted, what last week is being compared with, and whether payments can still go through.
```
### Clarifying Questions
- Does "transactions" mean successful payments, all attempted payments, or payment value, and does it cover every product (UPI transfers, merchant QR payments, wallet payments, bill payments and recharges) or only some of them?
- Is the 50% measured against the previous week, the same week last year, or a forecast, and was the comparison week unusual, such as a festival or a large sale?
- Is the drop nationwide and on both the app and the web, or concentrated in particular states, banks, app versions or merchant types?
- Did fewer people open the app and try to pay, or did roughly the same number try but fewer payments succeed?
### What a Strong Answer Covers
- Validation of the metric, the data pipeline and the comparison baseline before any product explanation.
- A decomposition of transactions (payers, attempts per payer, success rate) with cuts by product, payment rail, bank, platform, region, and consumer versus merchant side.
- Hypotheses ranked by how well they fit a sudden, very large drop, spanning technical failures, releases, regulatory or partner actions, ended incentives and market-wide events.
- For each hypothesis, the specific data or team that would confirm or rule it out.
### Follow-up Questions
- Payment attempts held steady but the success rate collapsed. Where do you look next, and whom do you bring in?
- The drop turns out to be concentrated in wallet payments right after a regulatory announcement. What do you do in the first two days?
- How would you set up monitoring so that a drop like this is caught within hours instead of at the weekly review?
Overview: A product manager interview question about Paytm: transaction volume fell by half in a single week, and the candidate must explain what could have caused it. It tests structured metric-drop diagnosis, from validating the data and baseline to segmenting the decline and weighing technical, partner, regulatory and market explanations.