Why Brainteasers?—What Interviewers are Looking For

Interviewers are looking for meaningful, uncontroversial conversations with candidates that will provide actionable information on which to make reliable selection decisions. Interviewers hope that puzzles and brainteasers will help create the possibility of such quality conversations.

Joel Spolsky, founder of Fog Creek Software and a former program manager at Microsoft, is an advocate of using brainteasers, primarily as conversation starters. “The goal is to have an interesting conversation with the candidate and to use that conversation to see how smart and capable they are,” Spolsky explains. “If you have an interesting conversation about certain types of topics with a person, you can determine if [he] is the type of person you want to hire. The questions are almost a pretext to having that conversation.”

In almost all cases, the interviews are less interested in the answer you get than in the road you use getting there. It’s all about process. To that extent, the best strategy is to take your time, think out loud, and let the interviewer see you sweat (at least a little). Ironically, solving these puzzles too fast may work against you. At a minimum, the interviewer may conclude you’ve heard the puzzle before. In any case, even if you impress the interviewer with your speed, you will have missed the opportunity to talk about how you would use the skills you just demonstrated to add value to the company. Let the interviewer participate with you in solving the puzzle.

The truth is, puzzles generally make up less than 10 percent of any job interview. “The puzzles are a small part of the interview process at Microsoft,” says Ron Jacobs, product manager for the Platform Architecture Guidance Team. “We’ve found it’s very effective in giving us insight into a candidate’s potential. And that potential is the hardest thing to gauge. We know the resume looks good and they seem to have the skills. These puzzles put them in a place where it’s just them and their raw thinking abilities.”

Jacobs says that the puzzles are usually designed so that there are no clear answers. Sometimes the interviewer will throw a candidate a hint that points to a solution that is clearly wrong, just to see how the candidate will defend his or her position and push back. “A level of confidence is good,” Jacobs says. “Microsoft is very much a company that values that kind of independent thought.” But don’t let the attitude slip into stubbornness or arrogance, he adds.

Jacobs speaks from experience. He should know, because he’s had three interviews at Microsoft. In 1997, in his first time at bat, Jacobs impressed people that he was a “Microsoft hire” but he was nevertheless thought not right for the position at hand. In his first interview, he was asked to design an airport. Jacobs immediately began to wax eloquent about how he would design a world-class international airport like Seattle’s Seatac or Chicago’s O’Hare. But after letting Jacobs go on for 5 minutes, the interviewer stopped him and said, “But all I need is a small regional airport.” Jacobs learned a lesson: “I didn’t clarify precisely what the customer needed.”

In his second interview a year later, Jacobs anticipated brainteasers but didn’t get any. He was asked to solve a coding problem instead. Since then, he’s interviewed for an internal job. “My take on the big picture here is that when we ask these questions we are looking not so much for the answer but how the candidate thinks about the problem and approaches the solution,” Jacobs notes. “Some candidates will be very quiet for a few minutes and then spew out an answer. This is generally a bad approach,” he says. “A better approach is for candidates to think out loud as though they were collaborating with me on the answer. I especially like to hear them ask questions which clarify the problem. Sometimes we will ask an intentionally vague question to test for this.”