7 insightful interview questions (and what they reveal)

Ask better questions to uncover what a CV can’t tell you

Modern talent acquisition is moving beyond gimmicky brainteasers toward evidence-based, psychologically insightful questions. Research shows that unstructured curveballs (e.g., “How many golf balls fit in a 747?”) don’t predict job performance.

Instead, today’s hiring leaders use probing questions grounded in behavioral science to uncover candidates’ true capabilities, motivations and fit. Such questions—often championed by top CEOs, talent experts, and organisational psychologists—help interviewers make smarter, science-led hiring decisions. In this article, we examine seven deep interview questions and the strategic insight each provides. Each question is attributed to a real source and backed by rationale and research to illustrate how modern, insight-driven interviewing can reveal the traits that matter most in a candidate.

“Tell me about some of the most difficult problems you worked on and how you solved them.”

This question, a favorite of Elon Musk in interviews, forces candidates to describe a genuinely hard problem they personally solved. Musk’s rationale is that real problem-solvers can articulate detailed solutions: “People who really solved the problem know exactly how they solved it. They can describe the little details.”

By contrast, a candidate exaggerating their role will stumble on specifics. In fact, Musk uses this prompt to spot false claims and test depth of problem-solving ability. It aligns with the Asymmetric Information Management (AIM) technique in cognitive psychology – truth-tellers tend to offer richer detail, whereas liars avoid specifics. In practice, this question reveals a candidate’s analytical skills, resourcefulness, and authenticity. The stories and depth of explanation indicate not only what they accomplished, but also their personal ownership of tough challenges. Candidates who thrive here demonstrate resilience and creativity under pressure, key traits for roles requiring innovation and independent problem-solving.

“What important truth do very few people agree with you on?”

Venture capitalist Peter Thiel is known for this provocative interview question. It asks the candidate to share a controversial belief—something they view as true despite most people disagreeing. Thiel explains that while the question sounds straightforward, it is “intellectually difficult” (because conventional answers won’t work) and “psychologically difficult” (because you must risk saying something unpopular).

In other words, it requires both original thinking and courage. The value of this query is the insight into a person’s independent thought process. A strong answer signals the candidate can challenge assumptions and offer fresh perspectives – a trait Thiel sees as a harbinger of innovation. This aligns with assessing creativity and cognitive diversity in hiring. By discussing an unconventional truth, the interviewer gleans the candidate’s willingness to dissent, mental agility, and confidence in their ideas. These are qualities important for roles that demand innovation or strategic thinking beyond the status quo.

“On a scale of 1 to 10, how weird are you?”

This famously quirky prompt comes from the late Tony Hsieh, former CEO of Zappos, who used it to assess cultural fit. Hsieh wasn’t looking for an exact number but rather the reaction and reasoning. As he explained, if someone claims “1,” they might be too straight-laced for a company that values fun; a “10” might be too psychotic.

The sweet spot is less about the number and more about authenticity and self-awareness in the answer. This question’s strategic value lies in uncovering whether the candidate will thrive in the organisation’s unique culture. It gauges a person’s comfort with individuality and how they might contribute to a “fun and a little weird” workplace (one of Zappos’ core values). In broader terms, it’s an assessment of Person-Organisation fit – the alignment between an individual’s personality and the company’s ethos. Hiring research shows that strong culture fit correlates with higher employee engagement and retention. An insightful answer here reveals if the candidate can be genuine and would feel at home in the team’s environment, which is as important to long-term success as skills or experience.

“Tell me about your failures.”

Jenny Ming, former CEO of Charlotte Russe, makes a point to ask candidates about their failures. While many candidates prefer to highlight successes, Ming is looking for those unafraid to discuss mistakes and setbacks. A good answer, she says, shows the person isn’t afraid of taking risks and will admit when things don’t work out.

The real focus is on what they did afterward: How did they handle the failure? What did they learn and change? By probing a failure, this question uncovers a candidate’s resilience, accountability, and capacity for growth. Candidates who can candidly discuss a failure demonstrate a growth mindset – an understanding that failure is a key part of learning and improvement. In modern, agile organisations, this mindset is highly valued because it means the individual will adapt, continually develop, and not shy away from challenges. Moreover, discussing a past failure tests a candidate’s emotional maturity and honesty. Those who deflect blame or cannot name a failure might lack self-awareness or fear taking responsibility. In contrast, high performers often embrace failures as learning experiences, showing they can turn setbacks into progress.

“Tell me about the last person you fired.”

For leadership roles, Marc Barros (cofounder and former CEO of Contour) swears by this tough question. He noted that among all his interview questions for executives, this one was the strongest indicator of leadership ability.

The reasoning is straightforward: if a candidate claims they’ve never had to fire anyone, it signals they may have avoided tough decisions or difficult conversations in their career. Great leaders need to build teams – and sometimes that means making hard calls to remove or reassign people for the greater good. Barros argues “you can’t build a great team without occasionally deconstructing and rebuilding it”. When a candidate does have a story about letting someone go, the how matters greatly. The interviewer listens for how the person handled the process: Did they communicate honestly and offer feedback? Were they empathetic yet firm? This reveals much about the candidate’s emotional intelligence, fairness, and courage as a leader. Ultimately, the firing question shines light on a leader’s management style: their ability to navigate sensitive situations, uphold standards, and care for team dynamics even amid difficulty. Leaders who do this well tend to act like coaches – giving constructive feedback and helping others grow – rather than avoiding conflict. It’s a telling indicator of whether a candidate can foster a high-performance team culture while making tough calls when necessary.

“Tell me about your crowning achievement.”

This question is a staple for Lou Adler, a veteran talent recruiter and CEO of The Adler Group. Adler always asks candidates to discuss their most significant accomplishment because it reveals multiple dimensions of their profile.

First, it highlights what energises and motivates the candidate – people tend to choose an achievement they found deeply meaningful or rewarding. As Adler explains, if you invest time in understanding someone’s proudest achievement, “then you know what motivates the person”. Second, it allows the interviewer to assess whether the candidate’s passions and strengths align with the role and company mission. For example, if a candidate’s crowning achievement involves leading a team to overcome a big challenge, and the open role values team leadership, that’s a promising sign. This alignment of personal passion with job requirements is crucial; when people work on what they care about, they typically exhibit higher engagement and performance. Moreover, the way a candidate narrates their top accomplishment can demonstrate drive, creativity, problem-solving, and their definition of success. Do they emphasise team credit or personal glory? Do they focus on overcoming obstacles or the impact achieved? These nuances inform the interviewer about the candidate’s values, work style, and level of ownership. Overall, asking about a crowning achievement is a positive way to understand a candidate’s core competence and intrinsic motivation – a key to predicting if they will thrive and find purpose in the job on offer.

“Give me an example of a time when you solved an analytically difficult problem.”

This question reflects the structured behavioral interview approach championed by experts like Laszlo Bock, Google’s former SVP of People Operations. Google infamously ditched its brainteaser questions in favor of behavioral questions like this one, after finding that brainteasers had zero predictive value.

Instead, asking candidates for a real example of solving a hard analytical problem accomplishes two things: (1) it shows how they actually behaved in a relevant past situation, and (2) it provides “valuable ‘meta’ information – a sense of what they consider difficult”. Bock notes that drilling into a candidate’s own experience yields far richer insight than hypothetical puzzles. The candidate’s story reveals their approach to complex reasoning, data analysis, and persistence. Equally telling is the scope of the problem they choose – what one candidate views as “difficult” might be routine to another, which helps calibrate their experience level and ambition. This technique is rooted in industrial-organisational psychology: behavioral interview questions (whether about analytical challenges, teamwork, or any key competency) are designed to predict future job performance by examining past behavior. Studies show that structured interviews with job-related scenarios or past-behavior questions have significantly higher predictive validity than unstructured chats. In practice, a strong answer to this analytic problem question demonstrates a candidate’s critical thinking process, problem decomposition skills, and intellectual curiosity. It also indicates their honesty in self-assessment – did they choose a truly challenging problem (showing ambition), and can they admit what was hard for them? For hiring managers, the responses to this question provide a research-backed window into how a candidate will tackle the real analytical tasks on the job.

Why insightful questions build stronger teams

Deeply insightful interview questions like these go beyond surface-level answers and tap into behavioral, cognitive, and motivational traits that traditional queries might miss. By learning from business leaders and talent experts – and grounding their techniques in organisational psychology – companies can refine their hiring process to identify candidates who not only have the right skills on paper, but also the right mindset, cultural fit, and potential to grow.

In an age where talent is a critical differentiator, leveraging well-crafted questions (backed by data and psychology) enables hiring teams to make more informed, bias-resistant decisions. The examples above illustrate how a strategic question can unveil a candidate’s true self: their problem-solving mettle, originality, resilience, leadership style, cultural alignment, passion, and more.

For HR executives and business stakeholders, incorporating such science-led interview practices can significantly improve the odds of finding high-performing, well-fitting hires – those who will thrive in the role and advance the organisation’s goals in the long run. By focusing on what really matters beneath the CV, we elevate hiring from a gut-driven art to a more precise science, without losing the human touch of a thoughtful question.