Design a bookshelf for children | Google PM Interview Question
Google Product Manager Interview Question: How would you design a bookshelf for children?
The core responsibility of a product manager is to drive product vision, design and development. A business decides to make a product because it has identified a real customer need for which the customer is willing to pay. It is the role of the product manager to identify customer needs and drive the design and development of products that meet those needs.
This product design interview question tests whether you understand the process of going from customer needs to product development. This process should involve defining who the customer is and what they want to accomplish; defining multiple use case scenarios in which the customer does activities that are related to your product, and prioritizing what to build.
What is the interviewer looking for?
The interviewer is evaluating you on the following:
Do you provide keen insights about the customer and their needs?
Are you able to provide multiple and diverse use case scenarios?
Is your answer structured and logical, or do you go off on a tangent?
Do you go beyond generalities in your solutions and provide detailed descriptions?
Can you provide ideas that no other candidate has mentioned?
Are you confident and sound credible? Would engineers and product people follow your lead?
How to structure your answer?
The steps of this method are:
C — Clarify. Ask questions to clarify what you are unsure of or confirm/disconfirm assumptions.
I — Identify the users/customers as personas like food lovers, soccer moms, etc.
R — Report on their needs (use cases). A use case is an activity that a user would like to do relative to your product.
C — Cut through and prioritize the use cases based on some attributes (revenue, customer benefit, complexity).
L — List solutions.
E — Evaluate the tradeoffs of your solutions.
S — Summarize:
State which solution you would recommend.
Recap what the solution does and why it is beneficial.
Explain why you prefer this solution.
How to quickly think of several use cases?
Use cases are at the heart of this question. Without use cases, you will have nothing to solve for. Because the interview is a conversation, you can’t ask for too much time to think about use cases. You can ask for at most one minute. This time constraint can cause anxiety because you need to think fast and then articulate your ideas almost simultaneously.
Sometimes we don’t have enough ideas on paper after one minute, or we are afraid of being silent and start answering immediately saying whatever comes to mind. The result is that we end up blurting attributes of a product or go straight to listing solutions without realizing that we haven’t described what kind of need or use case we are solving for.
Therefore, it is important to have a strategy or a method that triggers ideas for use cases fast. It is also important to articulate the use cases in a sentence that describes the user doing an action instead of just listing attributes of a solution.
Below are three strategies that can help spark ideas for use cases. Use the method or methods that you think will work best for you.
Method 1: Ask yourself the 5Ws
Start by asking yourself the 5Ws, in the order that is most useful.
Who is the user?
Why do they need to use this product?
What do they want to solve or do by using the product?
When will they be using the product?
Where will they be using the product?
By asking these questions to yourself, you may discover multiple types of users and use cases with different needs.
Method 2: Use word associations
Write down keywords from the question and circle them. Then think of other words or verbs that you associate with those keywords and connect them graphically with a line. If you have time, you can go one more level and connect other words to the previous words. As you are doing this, ideas for use cases will occur to you. Write down these ideas as bullet points using short sentences, if you have time.
Method 3: Use SCAMPER
SCAMPER is a technique to generate multiple and different ideas based on 7 actions:
S — Substitute something.
C — Combine it with something else.
A — Adapt something to it.
M — Magnify or Modify it.
P — Put it to another use.
E — Eliminate something.
R — Reverse or Rearrange it.
The objective of SCAMPER is to apply the actions to an existing product or service in order to generate new ideas for its usage. You could use scamper to think of use cases.
People get nervous when answering this question because they have to think on their feet. Below are some common mistakes people make:
Forgetting to ask clarifying questions.
Describing use cases as attributes that a solution should have instead of using sentences that describe what activities or tasks the user may do related to the product. For example, for the question “How would you design a bookshelf for children?”, saying something like, “the bookshelf should be durable, without sharp edges, and not too tall” is only listing attributes. The interviewer has forgotten to describe the use case that calls for those attributes. A better answer would be, “children have a tendency to stumble and fall, so the bookshelf should not have sharp edges.” Remember, the interviewer is looking to see if you think like a PM, and a PM doesn’t come up with solutions without knowing if the solution is meeting a critical use case.
Going straight to solutions without explaining what use cases those solutions are supporting.
Mentioning various use cases but forgetting in which order they talked about them.
Not clearly explaining what criteria they are using to prioritize use cases.
Not pushing themselves to think of original ideas, and ending up mentioning the same use cases or solutions that others have mentioned.
Forgetting to go into details about how to build a solution.
Forgetting to wrap up and provide a recommendation.
Ask Clarifying Questions
Q) Could you tell me what the desired objective is for the design?
A) We would like to design a bookshelf that stands out for its innovation, not just the usual usage of placing books or things on it.
Q) And where would the bookshelf be used? The obvious place is in family households but I can also see schools, children’s hospitals or any institution that deals with children using bookshelves too.
A) Let’s say it is for family households.
Q) And what is the age or age range of the children we are designing the bookshelf for?
A) Between the ages of 5 and 10.
State the Approach
The way I will go about answering this question is to first understand who the user or users are and what activities they would like to do relative to bookshelves. There may be some activities that no bookshelf serves today which could lead to innovative designs. After selecting some use cases, I will describe solutions and how to build them. Then I will wrap up with my final recommendation.
Parents are the most likely buyers of bookshelves for their children. Since the goal is to design an innovative bookshelf, I think the types of families buying such a bookshelf would be families with high disposable incomes. High-income families are likely to favor design over utility. Children will also use the bookshelf, so we will need to keep their behavior and needs in mind.
Listing Use Cases
Now I would like to think about different use cases, that is activities parents and children like to do that are related to a bookshelf. This will help spark new ideas for creating innovative designs for bookshelves.