How to Answer Product Design Questions
Product design questions ask you to design or improve a product. Common question types include:
- Design a product: “Design an app for job-seekers to match with employers.”
- Improve a product: “Improve headspace.”
- Design for a specific audience: “Design a vending machine for the blind.”
- “Moonshots”: A Google favorite — “Design X, assuming you have infinite resources.”
Overall, your goal is to come up with a feasible product given the constraints of the question. Feasible, in this context, means that your product solves a problem in a way that makes sense for the company and that users will like.
These typically take 25 minutes excluding follow-ups. Interviewers like to ask product design questions early on to filter out candidates who don’t have essential product skills, but they’re a popular question type during on-site interviews as well. Expect to answer several in a standard PM interview loop.
A framework for answering product design questions
A solid process is to first clarify the problem, gather relevant context until you understand users and their challenges, explore and select the best option, and finally, justify your answer. Follow this 7-step process.
- Step 1: Clarify and get context
- Step 2: Define users
- Step 3: Identify pain points and opportunity areas
- Step 4: Brainstorm possible solutions
- Step 5: Define a product vision
- Step 6: Prioritize features
- Step 7: Evaluate and recap
Let’s work through an example to illustrate.
Assume you’ve been asked the question “Design a better gym experience.”
Step 1: Clarify and get context
First, clarify any vagueness about the problem you’ve been given. After you’ve clarified ambiguous company names and keywords, gather context that will help you understand the problem space and define any strategic considerations that might influence your design.
Questions like “What’s the timeline?” or “Are there any constraints I should be aware of?” are fair game, but be prepared for an interviewer to give you a vague answer. In this case, make assumptions and state them to your interviewer so they have a chance to correct you if you’re veering off-track.
For our example question “Design a better gym experience” you’d want to ask a few questions to clarify the scope of the problem.
- “What do you mean by “gym experience?”
- “What is “better?” Are there any specific metrics we’re trying to drive?”
In addition, you could ask a few questions to help you understand the problem context and design from a perspective the interviewer is aligned with. For example:
- “Am I improving a home gym product or a commercial gym?”
- “Am I improving one particular gym location or for a chain?”
- “Am I improving a specific gym like Planet Fitness, or making general improvements?”
Let’s assume your interviewer doesn’t offer much detail. They say to you: “Make whatever assumptions you like; we just know that the gym experience works for some and not others and we want to make it better for more users.”
You state to your interviewer that, going forward, you’ll answer the question assuming you’re improving a generic commercial gym.
Step 2: Define users
Next, define subsets of users that would effectively partition the total user base and pick an interesting subset for a deep dive. There are many ways to segment users. To get started, you could consider:
- Demographics like age or income level
- Behavioral characteristics like frequency of use or users taking certain target actions
- Geographic location
Any of these is a good jumping-off point, but a great answer segments users in a way that is meaningful for the question at hand. One helpful tip is to segment users who might have very different needs. After choosing a segmentation scheme and listing a few basic user subsets, pick a segment that interests you and articulate why that segment is valuable to discuss. Consider:
- User subsets that may be strategic (for example, early adopters)
- Scale of impact, or the depth of pain that users feel
- How well you / your company can address these users in the context of your question
Continuing our example question “Design a better gym experience”, let’s say you decide to segment users according to their usage of the gym. Here are a few sample segments:
- “Pro” users
- Novice users
- Users who only take classes at the gym
- Users who have memberships but don’t actually go to the gym
Let’s say you want to target absent gym members.
”From this list, users who have memberships but don’t go to the gym stand out as a good segment for a deeper dive because they’re obviously experiencing an obstacle to achieving a goal. They were motivated enough to join the gym and are spending money on a membership, but something is preventing them from going. As an added benefit, I suspect we might be able to create value for other gym-goers and even attract new gym members if we solve this issue.”
Step 3: Identify pain points and opportunity areas
Next, consider any goals your users might have. Any explicit obstacles are pain points. If nothing’s blocking users from achieving their goals but some point of friction clearly exists, you’ve uncovered an opportunity area. Take an empathetic position and focus on how to best serve these users and you will uncover both.
Take a moment to summarize the goals you think your user subset has, then brainstorm pain points and opportunity areas preventing them from achieving those goals.
Use the "broad then deep" mini-framework to quickly hone in on key pain points.
Consider the circumstances users are in. Is the goal urgent? Are the decisions involved important or trivial? Asking yourself these questions and putting yourself in the user's shoes demonstrates user empathy, a key PM skill, so be sure to articulate your thought process to your interviewer.
Returning to our gym example, it’s clear that absent gym members had certain goals in mind when they bought their gym memberships. Their goals likely include some mix of the following:
- Getting healthier
- Looking better
- Gaining confidence
- Making friends (or at least being social)
What’s stopping these users from following through on these goals and using the gym? Your brainstorm could include emotional components like feeling uncomfortable at the gym. Discomfort might have many dimensions, including feeling intimidated or feeling bored.
Thinking about their circumstances, you realize that going to the gym is a decision they’re making from somewhere else - likely work or their homes. That creates logistical hurdles such as:
- Busy schedules
- Traffic
- A gym location that might not be convenient
Let’s say you decide to address the emotional hurdles rather than logistical hurdles as logistics will be more specific to each user and harder to solve:
"Users might not be going to the gym because they feel uncomfortable. Gyms can feel sterile and intimidating, which could prevent users who want to gain confidence or be social from using the gym. Gyms can also be boring, especially during peak times when users vie for limited equipment and might have to wait around awkwardly between sets.
It’s possible that users face a combination of emotional hurdles like feeling bored at the gym, and logistical issues, like a busy schedule, which would make it hard to decide to get to the gym after a busy or stressful day. If we can make the gym more compelling by solving the boredom or intimidation issue, the decision to go should be easier for my target users.
Going forward, I’d like to address the boredom issue at the gym. Specifically, the problem of waiting around for popular equipment to open up.”
Step 4: Brainstorm possible solutions
Now, brainstorm ideas that could solve the pain point you’ve identified.
To learn more about how to brainstorm product ideas, check out our guide.
One helpful tip for coming up with solutions is to think of products you like — especially anything solving a similar problem in another context. For example, Duolingo might be a good analogue for our gym example as it effectively removes barriers for people who want to improve themselves (by learning a language) but who have trouble with motivation, routine, or planning. The app is fun, easy to use, and the emphasis is on consistency rather than intensity. These are all characteristics you might incorporate into your design.
Aim to generate at least three solid ideas before moving on to the next step. It’s fine to brainstorm a bigger list and eliminate weak ideas. Check each idea against the pain point you identified and don't be afraid to get creative. Interviewers want to see excitement and passion for product.
Continuing our gym example, recall that you’ve decided to address the pain point of users feeling bored at the gym, especially during peak hours as users wait for equipment. Your brainstorm of possible solutions could include:
- Making the gym experience more customized through a workout recommendation system that accounts for peak hours
- “Gamifying” the gym experience so users feel more engaged at the gym overall
- Creating an activity specifically to fill the time between sets so users feel more engaged while waiting
Step 5: Come up with a forward-looking product vision
Pick the strongest solution from the previous section and take a moment or two to envision what that product will look like in five or ten years. Come up with a brief tagline that really emphasizes the point you're making. You want to leave the interviewer with a soundbite they’ll remember when they’re scoring your interview. Write it on the whiteboard (if you’re using one) and refer back to it as you continue.
Continuing our gym example, a forward-looking vision might look like this:
"A visit to the gym is made up of more than just the active time of working out, and that non-active time is often awkward or boring. In a futuristic gym, that time could be fun and exciting."
That could be enough for a short-and-sweet product vision, but if you want to add a bit more detail, you could finish with:
"Let’s build a gym that offers engaging activities available in between sets, helping users stay in the right mindset while getting a more effective workout.”
Step 6: Prioritize features
Once you’ve crafted a compelling product vision, it’s time to prioritize features.
We recommend walking the interviewer through a quick user journey where a user interacts with your product. This will help you concretely identify how your product fits into the existing user flow which will help you prioritize features. It’ll also help you stay user-centric instead of over-defining an idea that appeals to you personally.
Then, brainstorm a short list of features based on your use case(s) and prioritize according to which features best support your product vision. Be sure to tie the discussion back to user pain points. Here are a few helpful dimensions to consider:
- Scale: How many users does this help?
- Ease of expansion: How easily will this feature expand to other user subsets? Will it attract new users?
- Strategic impact: How well does this feature support the company vision?
You don’t need to describe every part of the feature in detail, but interviewers do expect you to describe what the user sees and interacts with and how that delivers on the product goals and vision you defined.
For our gym example, recall your product vision:
“Let’s build a gym that has supporting activities available in between sets, helping users stay in the right mindset and have more effective workouts.”
To begin prioritizing features, you might describe different specific approaches to supporting user's workouts. As you decided to focus on the problem of boredom between sets, it’s worth detailing that experience in a bit more detail. Ask yourself “What’s the process of waiting?”
“If you (a user) are standing around waiting, you’re typically either waiting to use a machine or taking a break between sets. We only have a small window; maybe five to ten minutes where we want to keep you engaged and entertained, but not distracted from your workout. Therefore our product should be a short experience that improves the user’s workout. For instance, we could create an app to log workouts and provide users with stats tracking, workout journal prompts, or tips and recommendations for their next set.”
Step 7: Evaluate and recap
As you wrap up, summarize your insights and your overall design for your interviewer, then spend a few minutes evaluating your design and discussing next steps. Consider:
- Tradeoffs you made
- Alternate use cases and edge cases
- What you’d do differently given more time
Common follow-up questions from interviewers include: “Can you see any risks with this design?” and “What challenges do you anticipate in implementing this product?” Discussing risks and challenges preemptively signals to interviewers that your ideas are grounded in reality.
To close the example question:
"One risk we should consider is that gyms are busy places with heavy equipment, so it could be dangerous if people are too distracted. We’d also have to make sure this doesn’t slow down users’ workouts or create more bottlenecks.”
Tips for answering product design questions
Consider company strategy
Bringing strategic concerns into the mix can help you reach a broader and deeper understanding of the problem at hand. Here are some prompts to consider:
- Company mission: What’s the company mission? Why does the company care about this space? How could this product support the mission?
- Company strategy: What are the relevant strategic goals the company might have? How could this tie into those or open up a new strategy? What products make sense strategically?
- Market understanding: What alternatives already exist in the market? Where are the gaps? What’s valuable in this market?
Ace moonshot questions by abstracting the problem
Moonshots are bold ideas that go beyond incremental changes. They’re frequently associated with Google interviews, but you can “moonshot” any design question by digging deep until you’ve uncovered the root of an important problem in a way that feels transformative.
You’re on the right track if you’ve found a way to solve the problem completely and simply for the user. If you’re able to eliminate the conditions that cause the problem in the first place, even better.
We've found two different strategies helpful for candidates practicing moonshots. One is to think of the product as a black box. The input is the user’s current state, and the output is the user as they want to be. By eliminating all assumptions about how to get users from where they are to where they want to be and exploring what could happen in that space, really transformative solutions can sometimes become clear.
Another strategy is to use something like the 5 Whys technique to dig deeper and deeper until you uncover the root of the problem.
You could also consider what the user’s actual goals are. For instance, if you’re asked to build an alarm clock for deaf users, consider that the user’s goal is to wake up at a certain time. Rather than limiting yourself to modifying how existing alarm clocks work, this framing allows for new options that rethink what an alarm clock is. Our best advice is to focus on the user and their needs — this approach will never steer you wrong.
Consider existing users, strategic goals, and market context when answering product improvement questions
Sometimes, you’ll be asked to improve an existing product. Questions like “Improve Instagram’s home tab” are similar to “design X” questions, but you’ll have to consider established users, goals, and market dynamics. Keep these in mind, and consider addressing under-served users, supporting new use cases, or adapting a product to open new strategic opportunities - these are all common areas for improvement.
Common pitfalls
- Jumping straight to a solution: make sure you explain your thought process so the interviewer can understand how you think and why your idea is a good solution. Also, don’t decide on a solution immediately after hearing the question. Keep an open mind, because you’ll usually find better ideas as you explore the problem.
- Forgetting to segment users: In some design questions, you’ll be given a subgroup of users or a constraint to design for, For instance, if you were asked: “Design Gmail for kids.” A very common mistake is to assume you don’t have to segment users because you’re given a constraint up front. For the Gmail question, kids are a broad group. You could segment out a particular age range or level of school to focus on. If you wanted to go deeper, we recommend discussing capabilities and constraints relevant to your segment. For instance, if your segment is early elementary school kids, some notable constraints would be that they’re not great at writing, they may not be very technically savvy, and their safety is extremely important. These will all influence the way you build your product, and they’re easy to miss them if you don’t explicitly consider them.
- Trying to design for everybody: If you try to design for everybody, you usually end up with something that nobody actually cares about. If you don’t narrow your scope, you’ll have trouble getting meaningful insights about your users and their pain points.
- Checking off the boxes: It’s okay to use a framework to keep yourself on track. However, the steps of a framework are recommendations to help you find insights, not a checklist you have to get through. Make sure you consider your answer holistically at every stage.