How To Answer A Product Design Interview Question 🌊

Context

Product design questions often come in the form: Design X for Y.

Examples include:

1. Design a social app for college students 🧑‍🎓
2. Design an application to help cheese connoisseurs purchase cheese 🧀
3. Design a surfboard for first-time surfers 🏄‍♀️

You may want to jump straight to some fantastic ideas you have for features. However, unless you have clear reasoning for your idea, it will be tough to convince your team of its validity. With that said, product design questions are a great exercise in applying structured thinking to a problem.

Interviewers are typically looking to see a clear, logical thought process to effectively build to a customer need, and a little creativity never hurts either.

Applying A Framework

Frameworks are helpful in that they clearly lay out a logical progression from problem to solution. Here’s an example framework applied to the “Design a surfboard for first-time surfers” question. To be clear, I have been surfing before but am certainly not super knowledgable in this area and you don’t need to be. Here are some key steps to follow:

1. Clarify
2. Outline your process
3. Customers — what are their needs and goals?
4. Gaps in current solutions
5. Brainstorm features and improvements
6. Prioritize solutions and identify trade-offs
7. Summarize recommendation

Photo by Vladimir Kudinov on Unsplash

What a simplified version of this interview could look like:

Clarify

Just to clarify, we are talking about surfing ocean waves? Are we shooting for any specific age group — young kids, teens, or adults? Just make sure you are on the same page as your interviewer and check any assumptions you’ve made already.

Outline

First, I’ll dive into thinking about our target customers and what their needs and goals are. Then, I’ll assess what needs are yet to be filled by products in the market and brainstorm some features to fill those gaps. Finally, I’ll prioritize the features in my solution and provide a final recommendation.

Customers

I’m going to focus on beginning surfers in their late teens and early 20s. I decided to target this group because surfing seems like a difficult sport to do when you are too young or too old because of the danger posed by being in the ocean, which can be quite unpredictable.

Although I’m not a surfer, I have seen beginner surfers struggle to get up on any waves — which seems like their main goal. They are typically floating on their stomach a lot, have a hard time dealing with the board, and I’ve even seen a few instances of people’s boards getting swept away from them onto the shore. Finally, I’d note that getting up for the first time seems like a big moment, one they may want to capture with a picture to post on Instagram.

Gaps/Features

I am aware of one type of beginner surfboard. It’s called the Wavestorm — it’s made out of foam, it’s quite long so it’s easy to ride, and it’s pretty cheap. The gaps in our customer’s problem that the Wavestorm fails to meet are:

1. It can be tough to handle because it is so big and bulky → an improvement here would be to make the board lighter and smaller. However, this would have the drawback of potentially making it harder to get up on.
2. The leash isn’t super sturdy and thus easily gets worn out, making it easier to be torn off of one’s leg while surfing → we could reinforce the leash to make it more durable and comfortable.
3. It doesn’t enable any sort of picture-taking → an improvement here would be to provide a place to easily attach a phone or camera (hopefully a waterproof one, such as a GoPro) to the front of the board. The drawbacks here would be a little extra weight and potentially some sort of hook protruding from the board that could get stuck on things.

Photo by NICO BHLR on Unsplash

Prioritize + Summarize

Given the needs and goals of a beginner surfer, I’d prioritize the following features:

1. Easy attachment for a phone or camera. This makes sharing the moment with others much easier and may provide more motivation to get up on a wave. The drawbacks are minimal.
2. A reinforced leash. This is also an easy win and will dramatically decrease the chance the surfer has a poor experience by losing their board to the waves.
3. Decreasing the weight and size of the board. This is tougher to do and has a huge drawback of making the board less stable in choppy waves.

That’s it! The key is utilizing a framework to focus on customers’ needs and clearly communicating your thought process. The final solution is not nearly as important as how you got there.

You can practice these types of questions with a friend, or also check out the following YouTube videos that show some great examples of diving into a question like this in more detail!

Best Mock Interviews

1. Design a product around movies for Facebook: https://www.youtube.com/watch?v=se6Soyi2k0U
2. Improve Spotify’s social features: https://www.youtube.com/watch?v=1dj0zA7jlGc&t=527s
3. Improve WhatsApp. Super great structure in answering this question: https://www.youtube.com/watch?v=e0Nj_eYDj2s