Equally worthless are the case interviews and brainteasers used by many firms. These include problems such as: “Your client is a paper manufacturer that is considering building a second plant. Should they?” or “Estimate how many gas stations there are in Manhattan.” Or, most annoyingly, “How many golf balls would fit inside a 747?”
Performance on these kinds of questions is at best a discrete skill that can be improved through practice, eliminating their utility for assessing candidates. At worst, they rely on some trivial bit of information or insight that is withheld from the candidate, and serve primarily to make the interviewer feel clever and self-satisfied. They have little if any ability to predict how candidates will perform in a job.
Full disclosure: I’m the Senior Vice President of People Operations at Google, and some of these interview questions have been and I’m sure continue to be used at the company. Sorry about that. We do everything we can to discourage this, and when our senior leaders—myself included—review applicants each week, we ignore the answers to these questions.
