Why I Prefer Whiteboard Challenges Over Take-Home Tasks in Senior Product Designer’s Job Interviews

A Product Design Lead’s perspective on why using them and what they can reveal

Take-home tasks are still a common part of Product Design hiring.

Give the candidate a problem. Give them a few days. Ask them to come back with a solution. Then schedule another meeting to review it.

I understand why companies use them.

But when I’m interviewing a Senior Product Designer, I usually prefer a whiteboard challenge.

Not because I want to see how quickly someone can draw boxes on a board.

And definitely not because I expect a polished solution in a job interview sesseion.

I use it because I want to see something that is difficult to see in a take-home assignment:

the candidate’s thinking while the problem is still unfolding.

How do they understand the situation?

What do they question?

What information do they realize they are missing?

How do they move from an observation to an actual problem?

What happens when the data doesn’t give them an obvious answer?

How do constraints change their decisions?

And eventually, how do they decide whether what they built actually worked?

That is the value of the exercise for me.

So in this article, I want to explain why I prefer whiteboard challenges over take-home tasks for Senior Product Designer interviews, what I believe you can learn from them, and how I personally structure mine.

Why not just give a take-home task?

My first reason is simple: the process becomes longer than it needs to be.

A take-home task usually means sending a brief, giving the candidate several days, waiting for the output, arranging another meeting, reviewing the work, and then discussing their decisions.

For a Senior Product Designer who already has case studies, I’m not always convinced I need another polished project.

Their portfolio should already give me evidence of their previous work.

I can use the case-study discussion to understand what they designed, why they made certain decisions, how they collaborated, and what happened after launch.

What I still don’t know is how they approach a completely new problem.

That is where a live challenge becomes useful.

There is another reason I’m cautious about take-home assignments.

They look standardized because everyone receives the same brief.

But that doesn’t mean everyone completes the task under the same conditions.

One candidate might have an entirely free weekend.

Another might be working full-time.

Someone might be sick.

Someone else might be interviewing with four companies at the same time.

One candidate might spend two hours on the task. Another might spend twelve.

And today, people also have very different access to help — from friends and mentors to templates and AI.

So the final output may reflect more than the candidate’s own decision-making.

A live session doesn’t magically make hiring fair. Interview anxiety, language, communication style, and different ways of thinking still matter.

But it removes some of the uncontrolled variables of a take-home task.

And it lets me observe the reasoning directly.

That idea is also consistent with how Cornell describes design whiteboard challenges: the goal is to observe real-time problem solving, clarification, assumptions, exploration, and communication — not simply the final artifact.

Before writing the challenge, I start with the role

I don’t think the right way to design a whiteboard challenge is to search for:

“10 difficult UX interview questions.”

The question should come from the job.

Before I create the exercise, I ask:

What does this Senior Product Designer actually need to be good at in this role?

If I expect them to work closely with Product Managers, understand metrics, participate in discovery, choose research methods, prioritize opportunities, work with constraints, evaluate trade-offs, and measure outcomes, then my challenge should give me a chance to observe those abilities.

The question itself doesn’t need to be complicated.

Actually, I prefer that it isn’t.

The complexity should come from the candidate’s decisions — not from trying to decode an intentionally confusing prompt.

This is also one reason I believe interviewers need some structure before running these sessions. Research on structured interviews recommends deciding which job-related competencies you want to assess first, then designing the interview around them rather than evaluating candidates based on general impressions afterward.

How I set up the challenge

I normally give the candidate around 35–40 minutes.

Before we start, I tell them:

“Think of yourself as the Senior Product Designer and think of me as your Product Manager. You can ask me for any information, context, or data you think you need.”

That sentence is important.

I don’t want them to treat the session as an exam where I secretly know the correct answer.

I want them to treat it like a product problem we are working through together.

Then I give them an observation.

For example:

Imagine we run a platform for transferring money internationally.

Week-one retention is 80%.

Conversion on the “Transfer Money” action is 30%.

The business wants us to increase conversion to 50%.

What would you do?

And then I let them lead.

The prompt is intentionally incomplete

The 80% retention number is there on purpose.

The business request is about conversion.

So I want to see what the candidate does with the rest of the information.

Do they understand what these metrics mean in this context?

Do they ask why the business wants conversion to reach 50%?

Do they question whether 30% is necessarily a bad number?

Do they ask what returning users are doing if they are not transferring money?

Do they want to understand user segments?

The funnel?

Previous research?

Changes in the product?

Data quality?

I don’t ask these questions for them.

I want to see whether they realize those questions need to be asked.

This distinction matters a lot to me.

If I hand the candidate the problem, the cause, the target user, and all the relevant data, then I have removed a large part of the work I expect a Senior Product Designer to be able to do.

In real product teams, we are often given observations:

“Conversion dropped.”

“Users aren’t engaging.”

“Retention is lower.”

“The business wants this metric to grow.”

Those are signals.

They are not automatically problem statements.

Can they resist solving too early?

Imagine the candidate hears the prompt and immediately says:

“We should simplify the money-transfer flow.”

Maybe.

But why?

We don’t know yet that the flow is the problem.

Maybe users don’t trust the service.

Maybe fees appear too late.

Maybe the exchange rate is confusing.

Maybe identity verification fails.

Maybe one acquisition source is bringing users with very low intent.

Maybe the target itself is unrealistic.

This is one of the main things I’m looking for:

Can the candidate move from

Observation → Investigation → Evidence → Hypothesis → Problem

before moving to a solution?

I don’t care whether they use those exact words.

I care whether that logic exists in their thinking.

Research method names don’t impress me very much

At some point, candidates usually want more evidence.

Great.

But saying:

“I would do user research”

doesn’t tell me much.

If they choose interviews, I want to understand why.

What are they trying to learn?

Who would they talk to?

What questions would they ask?

Why an interview instead of a survey?

Why not analytics?

Why not usability testing?

Why not session recordings?

The method should come from the question.

NN/g makes the same point in its framework for UX research methods: different methods answer different kinds of questions, and choosing between qualitative, quantitative, attitudinal, and behavioral approaches should depend on what you are trying to learn.

I may also introduce constraints.

Maybe they say:

“I would interview users.”

And I tell them:

“Assume we can’t run interviews right now.”

Now what?

Do they freeze?

Or do they look for another source of evidence?

Existing analytics?

Support tickets?

Previous research?

Session recordings?

A smaller usability study?

I care about this because product teams rarely give designers unlimited time, budget, research access, and engineering capacity.

A process that only works under perfect conditions isn’t particularly useful.

Then I make the data less convenient

Suppose the candidate decides to conduct hypothetical interviews with 20 users.

Based on the questions they ask, I might give them something like:

8 users mention Problem A. 8 users mention Problem B. 4 users mention Problem C.

Now I want to see what happens.

There is no obvious winner.

A and B have exactly the same frequency.

Do they simply pick one?

Or do they start asking better questions?

Maybe one problem is more severe.

Maybe one affects a more important segment.

Maybe one has a stronger relationship with the business goal.

Maybe one has higher potential impact but much higher implementation cost.

Maybe we don’t have enough confidence yet.

Maybe we should validate one assumption before investing in either solution.

This is one of the moments where I can see whether someone knows how to turn research into a product decision.

Because research findings don’t usually arrive prioritized for us.

Someone still has to make the decision.

I want to see trade-offs, not an ideation performance

Eventually, we reach solutions.

I don’t need fifty ideas.

I just don’t want the first plausible idea to automatically become the solution.

Maybe one direction is quick but limited.

Another could have much greater impact but requires significant engineering work.

Another might be the strongest long-term direction but impossible within the current deadline.

What would they choose?

Why?

What are they optimizing for?

What are they giving up?

What could they test first?

I’m interested in whether the candidate understands that product design is often less about finding a perfect solution and more about choosing between imperfect options.

The most interesting part might happen after the solution

The candidate eventually proposes a direction.

For me, the exercise still isn’t finished.

I want to see whether they start talking about measurement.

Suppose we launch the solution and conversion moves from 30% closer to 50%.

Can we say:

“Our design worked”?

Maybe.

But I want to see whether the candidate recognizes that other explanations could exist.

Could acquisition have brought in a different user segment?

Was a marketing campaign happening at the same time?

Did seasonality affect transfers?

Did our instrumentation change?

Did every user see the new experience?

What happened to our guardrail metrics?

Did conversion improve while another important metric became worse?

Again, I am not asking these questions for them.

I’m looking to see whether they think about them.

Because:

“The metric increased after launch” is not the same claim as “our design caused the metric to increase.”

That difference matters.

And then there is another question:

What happens if the solution doesn’t work?

Do they immediately redesign?

Or do they return to the hypothesis?

Check implementation?

Check tracking?

Look at segments?

Revisit the evidence?

Question whether they framed the correct problem in the first place?

For me, seniority also shows in what someone does when their original assumption turns out to be wrong.

Why 35–40 minutes?

The time constraint is part of the exercise.

Not because I want people to think quickly.

I want to see how they manage limited time.

Can they avoid spending almost the whole interview researching?

Can they avoid jumping into solutions after three minutes?

Do they know when they have enough evidence to make the next decision?

Can they say:

“I don’t have enough information to know this with certainty, so for now I’m going to make this assumption and continue”?

That is a very normal product decision.

Perfect information doesn’t exist.

Time management, prioritization, and knowing when to move forward are part of the work too.

The interviewer has work to do as well

None of this means simply giving someone a random whiteboard question creates a good interview.

The interviewer needs to know what they are trying to observe.

For me, those signals usually include product understanding, problem framing, question quality, research judgment, collaboration, prioritization, trade-offs, awareness of resources and constraints, time management, measurement, and the ability to adapt when new evidence appears.

For another Senior Product Designer role, the list might be different.

That’s fine.

It should be different if the job is different.

What matters is that the expectations come from the role rather than being invented after meeting the candidate.

That is one of the main benefits of more structured interviewing: candidates can be evaluated against job-related competencies and more consistent standards rather than purely on interviewer intuition.

What I want to know after 40 minutes

At the end of the session, I’m not asking:

“Did they find the right answer?”

There isn’t one.

I’m trying to answer a different question:

Would I trust this person with a real product problem?

Would they know what to question?

Would they know what information they need?

Could they turn an observation into a properly framed problem?

Could they choose an appropriate way to validate their assumptions?

Could they make a decision when the data is messy?

Could they work with limited time and resources?

Could they explain their trade-offs?

And after launch, would they know whether we actually improved anything?

That is why I prefer whiteboard challenges over giving another take-home task when I’m interviewing Senior Product Designers.

The output is not the most interesting part.

The decisions that produce it are.