asked in Product Design by (1.1k points) | 1.3k views

6 Answers


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

answered by (47 points)

Redesign – Question equates to that something exists today & we would have redesign or make changes in such a way that it achieves either its standard objectives or new objectives.

The way I would approach this question

Interviewer : How would redesign the carwash ?
Me: Hmm.. Very interesting question . May I ask you couple of clarifying questions please.
Interviewer : Sure
Me: Do we know what type of Car wash we are trying to redesign . Example includes completely automatic , Partially , Self cleaning manual or manual by person carwash. Does Carwash wash passenger cars & does it include Commercial Trucks ?
Interviewer : Lets just focus on Self cleaning manual for passenger car ( Where driver has to come outside & clean the car using provided equipment
( I narrow down the problem )

I would immediately go into shoes of consultant who is directly working with owner of car wash company.

Me: Thank you. Let me think about it for a minute.
Me: Lets first set the objective of redesigning. Do we know why do we want to redesign our cash wash . Example would include we are experiencing decline in the footprints , revenue & hence we want to improve our core revenue. Other objective could be we are hearing lot of complaints about experience of customer & we want to make it better in terms of services & experience. Add more services into car-wash to earn ancillary revenue.

Interviewer : You may assume All.

Now consultant would ask for data for current transactions & about customers but PM would take product & customers in mind & start laying out ideas around potential issues in achieving each objective.

I would immediately goes into shoes of Product Manager ( Owner of Car Wash ) . Just think you are owner & its your OWN money on the neck. What you do ?

Discuss Potential Issues keep footprints , experience & other services in mind

A) Cumbersome & hard to understand process – When customer arrives , it is hard to understand all the available options & customers gets confused which ones to use. Example : Wax Rinse , Rinse After/Before , Tire Special Rinse, Soft Foam , Hard Foaming Brush , Initial Rinse. This may sway away some customers

B) Waiting for the turn – Its hot & customers dont want to wait . Or least customers want to wait in shed. Long waiting lines would discourage repeat customers.

C) Driver cleans the car but spouse,kids get bored. Nothing to do. More Worse wait in open & child safety in question.

D) Pay by coin but not sure where to get coins . Customer turning away. Easy Payment options

E) Water Sprayer Pipe very hard to navigate & keep on interfering with car. Multiple equipment for different options adds to the complexity of process. Water Pressure Points etc.

F) Dirty Surface floor & slippery too . Customers feared about safety sometimes.

G) Equipment not working properly & not timely respond by maintenance.

Me : These are some of the problems that I believe could reduce footprints hence revenue , bad experience , lower repeat business & leaving opportunity of ancillary revenue. Lets brainstorm some ideas how could fix these issues.

Potential Ideas

A) Clear digital chart in form of animated video , helping customers to understand benefits of each option & when to to use . Pros – Customers use more options , means more revenue per customer visit . Cons – Creating the content , Digital TV & maintenance.

B) Waiting issue :- Increase number of bays , Create a app for scheduling that provides code & time. Customers directly goes into car wash at scheduled time & fill in the code to get in line . Walk-in customers has separate queue but could enter the bay if no scheduled customer is expected. For one with waiting , create cloth sheds to avoid summer hot. Pros – Better Efficient Process & less wait times. This means better loyalty & experience. Cons . Capital investment & might increase prices . So need to very verify whether target customer willing to pay for that.

C) Family gets bored either in car or outside the car. Create a waiting room. Set up Vending machines . Pros : additional revenue sources , better Experience . Cons – Cost intensive & will increase prices for car wash.

D) Credit Card payment , Pay by App & input Code etc. – Pros : Customer Experience. Cons – Increase Cost.

E) From Operation Perspective – Make the navigational square metal frame on celing . This will make sure pipe will not interfere with car . Same equipment for soap & water based on option selected but provide separate free hand brush . Pros : Significantly easy to do self car wash. Reduces cost .

F ) Dirty & Slipper Floor – Automatic cleaning of floor every 4-5 car washes along with Dryer. Strict Penalities for any car fixes , Oil changes etc. enforced by cameras & License Plate sensors.

Me : Finalize I will prioritize the features & Recommend to implement A , B , C.

answered by (43 points)
+1 like

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

answered by (41 points)
+1 like

I would ask by clarifying the objective of re-designing the car wash. is it increasing revenue or customer experience. Assuming the objective is to increase revenue. I will also clarify that we are talking about the car wash in the US that can service majority of the consumer cars. Having said that i want to think about few pain points that i see today while using the car wash, discuss few ways of mitigating those challenges, brainstorm the benefits and challenges of each and than make a recommendation on the design. I would assume that the car wash includes both automatic and manual car wash.

Major pain points for users are:
1) Wait time – Typically consumers arrive at car wash after work and usually have to wait for few minutes before the service. This has discouraged me with at times from using the car service.
2)Quality Concerns – In the automatic car wash, as a user i am always concern about if the robotic arms used in the car wash were properly calibrated and the mops they are using are clean so that their is no mark left on my car. This becomes more important as we talk about premium category of cars.

To address these consumer pain-points I have a couple of options:

1) Desktop website/application – This can let users reserve the car wash in advance so that their is more predictability in service time. i will also let consumers choose an option to have the car wash at a regular cadence. i will integrate the payment service in the application.

2)Install cameras – i will propose that we take close pictures of the car before and after the service so that consumers have peace of mind that their car is cleaned well and their are no damages to the car because of robotic controls in the car.

3) SMS service – Although smart phones are common in the city, many users are still using non-smart phones. In order to reach out to those customers, I will think of an SMS service where consumers can text and reserve a slot.

2) Promotion Programs – I will start a loyalty program where customers get a free car wash after X number of car washes. Offer discount to regular customers, invite customer for a car wash after a storm, offer different bundles of service such as monthly car wash for a reduce price, discount for 1st time customers etc.

I will choose launching an application as it addresses all pain points and images of the vehicle can be uploaded the the customer account itself. Although, developing an app will require capital investment for the service and the car wash service might have to outsource development to a 3rd party as they don’t have expertise in it.

answered by (45 points)
+1 like


  1. Who do we want to re-design the carwash for? Assume for private car owners
  2. Why do you we want to re-design this? Is there an ulterior goal? No
  3. Are we talking about manual or automated car washes? Both
  4. What scale are we talking about? National carwash company
  5. Timeline to complete this? ASAP

Customer Pain Points

  1. Slow - car washes can take time, and people often can wait hours for it
  2. Inefficient - many car washes are run by humans, with humans cleaning your car
  3. Many different types of washes - choice paralysis
  4. Inconvenience of location - not everyone has access to a car wash


  1. Bring the the carwash into the digital age, with applications on wait times and locators. A mobile application can help users more easily se how long the lines are and where they can wash their cars. This will also help them more easily understand what their options are. 
  2. Fully automated car wash location, wherein you do not need to interact with a human to have your car washed. From the point-of-sale to the actual washing, can we have customers only interact with a machine? 
  3. Improve the locality of car washes, such that they are located in places where people congregate and park. This includes mall parking lots, downtown areas, and any town center. 
  4. Simply the assembly line of a car wash, by making each person there a specialist in a specific car wash element. At scale, each person is only responsible for a certain piece, thus making the process much faster. 

Prioritize Solutions

I'm going to take a big swing here and incorporate many of the above ideas. I would like to build a car wash, which is able to travel around a parking lot, and is able to almost fully automate the entire washing process. I envision this machine as a huge truck like car, with two arms that can surround a car. These arms are responsible for the wetting, washing, and drying of the car. With a fully mobile solution, large parking lots can rent this machine, and operate it in their parking lot. Lots can then have a section of the lot, with larger parking spots, where the automatic car washing machine can do its job. Customers then pay the lot for the wash, and designate their cars for the wash. This model is scalable, as the operations are franchised out, and is almost fully automatic. 
  1. One downside of this solution is that it may be too efficient, and will actually waste water with too many car washes. That's bad for the planet, so in this design process, we also must take into a account a water efficient method. Maybe we can try using sprayers to mist instead of spray the cars. 
  2. Another trade off is that this solution is likely years into the future. If we assume self-driving cars are going to reduce private car ownership, the value of a car wash will diminish for the private car market. But this solution can also be used for non-privately owned cars. 
answered by (25 points)

Improving a carwash

What is a carwash?

  • It's a service where motorists pay for their vehicle to be washed.
  • Let's assume we're limiting this a drive-in carwash - i.e. one that anyone can accesss.
  • A carwash can be automated or manual. Let's assume this one is currently a mixture of both.

Who are the users?

  • Individuals
  • Businesses

What's the goal?

  • User satisfaction
  • User acquisition/retention
  • Visits per user
  • User spend per visit
To decide which of these to focus on I'd need to understand each of these in the context of industry benchmarks. I'd also need to understand the carwash's market share and the size of the total addressable market.
In the absence of data, my suspicion would be that the goal would be to increase user spend per visit since capacity is fairly limited in the short term.

What are we improving?

  • Users want to get their car cleaned for them for maintenance (i.e. avoid rust) or to make it look better.
  • There's a minimum standard to meet for maintenance so let's focus on making it look better. This can be divided into personal and business purposes.
  • A business (like a tradesman, taxi, company car) might see the risk of losing money if their vehicle is dirty. A private individual might fear looking bad in front of their peers.
I'd want to look at how much each group is spending per visit and look at how that's distributed. I'd assume businesses already spend more but that it's unevenly distributed. So i'd want to look into how to improve spend for the mid and low spenders within each category.

What would we build?

I'd assume that businesses that make less money per vehicle might be spending less money on washing it and go for the minimum. I would aim for lower end taxi companies (rather than black car/limousine services). I'd want to improve uptake of higher value services within that user group.
Without being able to speak to users, I would assume the following opportunities:
  • As a cab driver that picks up passengers frequently, I want to get a gloss/wax finish on my vehicle so that I'm selected by passengers on the street.
  • As an Uber/Lyft driver, I want the inside of my vehicle to be exceptionally clean so that I get a good rider rating.
  • As a busy driver I want to be able to buy other services for my vehicle (like accessories, repairs etc.) so that I'm able to maximise time on the road.
My assumption is that the product focusing on Uber/Lyft drivers wil be most effective since that's a growing segment (for now).

How do we implement and test?

Ways of increasing sales of internal cleaning/servicing:

  • Offer promotion to drivers for an internal clean (free/discounted)
  • Introduce new upsell services (like air freshners, bottles of water for riders, aux cables for riders to play music)
  • Extend product lines to higher margin, luxury products

Of these, the simplest to implement is the promotion, applied to this segment of drivers.

  • I'd look at what proportion of drivers re-order the service and cost that against the cost of labour for offering it.
  • If this proves effective, a similar technique can be applied to one-offs of new product lines, ranked by cost of implementing in the long term versus size of market.
  • Alternatively, it can be applied to other user groups. Or the approach can be refined by improving messaging/targeting/channels.
  • I would watch out for harm caused by increased wait time for other users


  • Focus on spend per visit
  • Target low-spending business customers
  • Specifically target Uber/Lyft drivers with an internal vehicle clean

answered by (22 points)

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