Exercise 98 – How would you re-design the carwash?

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See also:

How to answer a product design question in a product manager job interview

List of product design questions for product manager job interviews

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Clarify the ask: Is this a industrial car wash or a regular car wash at gas stations? Is it fully automatic or partly automatic? Up-to what size car is it capable of washing?
Lets assume this is a regular car wash capable of washing cars up to Full-size SUVs.

Goal: Easily wash cars of all sizes up-to full size SUVs.

Customers / Users:
Private car owners: These can be segmented by age, profession, education, income levels
Enterprise car owners: Cab/Uber drivers, Rental car owners etc.

Use Cases:
Wash cars (Cant think of anything else)

Competition Pain points:
1. Most car washes use a lot of water
2. No way to check if all dirty spots are cleaned
3. Do not dry the car completely
4. Get water spots if windows are rolled down and up again

Features to solve / Tradeoffs:
1. Waterless car washes or low water use car washes / Complex and expensive to develop, hence raise price
2. Compare before and after pics using image processing / Complex and expensive to develop, hence raise price
3. Identify and air dry wet spots iteratively / Would increase cycle time
4. Same as above

Based on customer benefit, complexity and cost to implement
#2, #4, #1, #3


We could start by asking what we are trying to achieve. Are we talking about manual car wash shops or automatic?
Since manual wash takes longer, but provide better results, let´s assume that this will be the case.
What are we trying to achieve?
Should the car wash:
– be faster?
– use less water?
– provide extra value added services to drivers? Waiting room with TV, internet, snacks, coffee?
Let´s assume we want to increase the user experience by minimizing lines and waiting times and providing extra services while the client waits to have her car washed.
Let´s also assume that the typical car wash client is women who work during the week and don´t have much time.
Possible solutions:

– App where the client could schedule a time for having her car washed. The app could offer loyalty and discounts to retain customers. For each appointment, the client would get a voucher for a free coffee in the lounge area. Payment would be integrated in the app. Partnerships with Food Delivery services could be established, so the client could order dinner to go and get it delivered during the time window when the car is being washed.
What we could do first:
1 – Implement the scheduling feature
2 – Integrate payment
3 – Implement discounts/vouchers
4 – Integrate with food delivery services