Product Sense: Make a Vending Machine Usable Without Sight
Company: Microsoft
Role: Product Manager
Category: Product Design & Strategy
Difficulty: medium
Interview Round: Other
You are the product manager for a vending machine, and customers who cannot see need to be able to use it. Propose the product.
```hint Walk the purchase without sight
Go through every step of buying from a vending machine, from finding it to checking what came out, and ask what information a sighted customer gets from their eyes at each step.
```
### Clarifying Questions
- Is this a new machine, or a change that can be retrofitted to machines already in service?
- Will the same machine also serve sighted customers, or is it dedicated to a specific setting?
- Which payment methods must it accept: cash, cards, phone wallets, or all of them?
- Can the design assume customers carry a smartphone with a screen reader, or must it work without one?
### What a Strong Answer Covers
- The users involved: blind customers with different skills (braille readers and non-readers), sighted customers and the machine operator
- The end-to-end purchase journey, with the specific barrier at each step
- Solutions for browsing, selection, payment, change and item retrieval, with a prioritized first version
- Trade-offs between audio, tactile controls, voice input and a phone companion, including cost and privacy
- How success would be measured and tested with blind users
### Follow-up Questions
- How would the customer know the item they received is the one they paid for?
- How would you keep the menu accurate when the operator restocks the machine with different products?
- How would you convince the operator to pay for these changes?
Overview: A product design question asking the candidate to design a vending machine that blind customers can use on their own. It tests mapping the purchase journey without sight, weighing audio, tactile and phone-based solutions, prioritizing a first version and measuring accessibility outcomes.