Design a Refrigerator

A common practice in product interviews these days is to ask the candidate to design something from a product perspective. The product design question could come in a variety of forms. For example, interviewers could set up the question by asking you what your favorite (or least favorite) app is and then proceed to ask you how to improve it, or possibly even design it’s competitor. Alternatively, the product design question could come in the form of something completely different with your interviewer asking you to design a fridge. In fact, I have been asked this very question by a well known Silicon Valley company during the interview process. All this to say, if you’re unfamiliar or not used to this type of questioning, I’ll walk you through the general approach to product design questions.

Set the Stage

First things first, one thing I like to recommend to all product manager interviewees is that they go old school and have a pen and paper at the ready (yes, even for virtual interviews). The reason behind this thinking is that it helps to write down the questions you’re asked during the interview, capture notes and feedback, and even strategize your answers during the course of the interview. Also, don’t be afraid to ask for a few moments to think about your answer and jot down your thoughts on paper as you work through the question. In fact, if you don’t ask for some time to consider your response during your product design question, that can sometimes be viewed as negative. The interviewer may start to think that you are someone that tends to rush into solutions rather than consider the scenario you are presented with.

Gather Information

Once your interviewer has presented the product design question, it’s time to get as much information as possible about the design scenario. Begin by considering these three primary questions: why are we building this, who are we building this for, and how do we know if it’s successful (you can learn more about these three questions here: 3 Questions for Empowered Product Teams). Using this framework can help to target your questions appropriately in order to learn if your interviewer has more information that they are hoping you will uncover.

I want to take a moment here to also mention that sometimes you will be in interviews where the interviewer provides no additional information to help frame the product design question. This could be for a variety of reasons, one being they are intentionally leaving the question as open as possible in order to see how the candidate performs in an ambiguous problem space. Other times, to be frank, it may simply be because the interviewer did not prepare enough for the interview and has no additional information because they themselves have not considered the proposed scenario beyond the initial question. In any case, if you find yourself in this scenario, where the interviewer provides no additional details, it is incredibly important to think out loud and talk through your assumptions and considerations as you develop your response (and also keep checking in with your interviewer as you work through your answer).

Understand Why

Now that you feel comfortable with the general concept of the product design question, and you (hopefully) have some additional information from your interviewer to help frame up the problem, it is time to figure out why this product is being built.

This is where the ‘why’ part of the question is uncovered. The goal here is to learn why this product is being created in the first place. Why does this product need to exist? What problem is it solving? Why work on it? Your goal here is to develop a ‘why’ behind the product and articulate your reasoning behind the ‘why’ you have devised. As some guidance, it is perfectly fine to draw upon experience and similar products to draft your ‘why’. You may have encountered this problem yourself in which case you may be able to passionately describe why this product absolutely needs to exist.

Eventually, after developing a strategy surrounding why this product is worth pursuing, you may even find yourself in the midst of a vision statement to help inspire and form the basis of a strategy around the product. If you are able to put a vision together then by all means write that down and relay it to your interviewer. Also, perhaps use this time to describe how important a vision is to products and how you ensure that the product vision is always part of your approach in product development.

Understand Who

Now that the product has a reason for existing, it is time to try to understand what sort of market you’re working with.

Consider here the types of users that would benefit from the product you’re designing. While controversial at times, the use of user personas can be an interesting concept to discuss in order to help refine just who this product is for. This is also a great time to circle back with your interviewer to chat about the types of users you think could benefit from the product and see what their thoughts are on where you’re heading with your approach. You may find that the user persona/segment/cohort that could benefit from this product also aligns with users you have built products for in the past, in which case you can mention that in the interview and leverage that experience to develop a more detailed explanation.

It is important to mention here that it is useful to have a rough understanding of population numbers relative to where you live. For example, I always try to have a rough idea of the population of the United States and then also a general estimate for the population of California. This allows you to dive into the total addressable market for the population that could benefit from this product. If you are able to quantify approximately how many users you believe could benefit from your product then that is a fantastic answer to add to your design evaluation.

Understand Outcomes

You have now reached the point where you should have a better understanding of the problem space surrounding the product. You should be able to articulate why this product is worth pursuing and who you are building this product for. Also, you should have an idea of the total addressable market as well as any other pertinent information the interviewer has passed along.

You should now be at a point where you can start to think about the problems you are solving with this product and the subsequent outcomes you aim to achieve. This is a good time to discuss your approach in how you consider product discovery when it comes to outcomes. How do you uncover problems to solve and outcomes to deliver? Do you like the ‘product triad’ approach where you (serving as product), the UX representative, and the engineering representative conduct discovery sessions to help develop how best to solve the problem(s)? Do you like to use customer surveys to help collect information? Do you look at analytics to help derive the best approach? Do you use focus groups or prototypes to help guide the design process? Or, something else entirely? Whatever your preferred approach is, now is the time to discuss how you like conduct your discovery work in order to locate the problems to solve and the outcomes you aim to achieve. The goal during this part of the product design question isn’t to come up with the best features, solutions, or outcomes but rather to discuss your reasoning behind why you believe your proposed outcomes are the ones worth striving for in order to best serve your target market.

Understand Priority

At this point, you are now able to describe why you are building this product (vision), the users you are building this product for (who), and the list of problems you will solve when you deliver for your product (outcomes).

You may find that this is enough for some interviews, but if not, it is now time to discuss how you would go about prioritizing these outcomes and potentially discussing how you would lay them out on a roadmap.

Prioritization is a very important activity for product managers as it helps to convey the strategy behind a product. In other words, the delivery order of outcomes communicates how the product team is working towards achieving the vision for their product. Items to consider at this point may include things like the highest impact problems to solve, the make up of the development team (for example, are vendors involved?), the roll out strategy (is this for a specific market or region of the world?), as well as what outcomes are not worth pursuing.

There are many prioritization frameworks to select from when considering how best to prioritize your outcomes (including the Simple Prioritization Framework). Try not to worry about which prioritization framework you select, but rather that you can describe it quickly and succinctly and that your interviewer can easily understand how you prioritize the work.

After this part of the interview, if your interviewer believes that you think about prioritization and that you have solid reasoning behind your prioritization approach then you have executed this section perfectly. Bonus points if you can also put these outcomes on a roadmap.

Understand Success

You should be feeling pretty good at this point because you now have a well developed answer to the product design question along with a list of outcomes you will achieve. But, how do you know if you will be successful? How can you justify the direction of the product?

The answer? Success criteria. This is where interview candidates separate themselves from the rest of the competition. When considering success criteria, think about the current state of the product and the goal state for where you want the product to strive towards.

There are some helpful frameworks available to communicate how you intend to measure and report the success metrics for your product that you should review and take advantage of (for example, the HEART Framework). Additionally, if you can discuss how you would empower your team to be aware of and champion the success criteria then that is a fantastic consideration as well (hint, dashboards). Please keep in mind that success metrics can also be utilized to decide whether or not to stop work, which is valuable to consider as well in the development of your strategy.

Being able to discuss success criteria with your interviewer shows that you are not someone that just builds features for the sake of it, but rather, you pursue outcomes and measure the success of those outcomes.

Wrap Up

The product design question can be an intimidating question when first encountered. It is best to systematically approach these questions with enthusiasm as you break them down and develop a strategy that both you and your interviewer are proud of.