Product design case: reimagining how a car wash works
Company: Google
Role: Product Manager
Category: Product Design & Strategy
Difficulty: medium
Interview Round: Other
You are a product manager asked to redesign the car wash. Work out what the redesign should achieve and for whom, find where today's car wash experience breaks down, propose and prioritize changes, and explain how you would know the redesign worked.
```hint Fix the format first
Car washes run very differently: self-service bays, drive-through machines and staffed hand washes. Settle which one you are redesigning, then follow one customer from noticing the car is dirty to pulling away, and note where time, effort or uncertainty piles up.
```
### Clarifying Questions
- Which kind of car wash is in scope: self-service bays where drivers wash the car themselves, automated drive-through washes, or staffed hand-wash and detailing services?
- Are we redesigning for an existing operator, anywhere from a single site to a national chain, or entering as a new business, and which outcome matters most: more visits, more revenue per visit, happier repeat customers, or lower operating cost?
- Should the redesign serve private car owners only, or also rideshare drivers, fleets and commercial vehicles?
- Are water use, energy use and local environmental rules in scope as constraints?
### What a Strong Answer Covers
- A stated objective for the redesign, agreed before any ideas, and the business it serves
- A chosen car wash format and customer segment, compared against the alternatives, with the reason for the choice
- Pain points drawn from a full visit, ranked by how much they cost customers or the business
- Changes prioritized on impact, effort and site realities such as capital equipment, throughput per bay or lane, and staffing
- A primary success metric with guardrails, plus risks such as vehicle damage, safety, water use and higher prices
### Follow-up Questions
- How would you test your top change at a few sites before rolling it out everywhere?
- If the redesign cut wait times but more customers complained that their car came out less clean, what would you change?
- How would your plan shift if shared or self-driving fleets came to own a large share of cars?
Overview: A product design interview question that asks a product manager to rethink how a car wash works. It tests whether the candidate clarifies which kind of car wash and which business goal are meant, picks a customer segment, maps pain points across a visit, prioritizes changes against cost and site operations, and defines how success would be measured.