The list, released late Monday, includes the sort of questions that would make many job hopefuls freeze. "How many basketballs would fit in this room?" was a question one Delta Airlines candidate reported hearing. "When a hot dog expands, in which direction does it split and why?" was a reported question for a Propulsion Structural Analyst job at SpaceX.
It's hard to know how frequently such questions are actually asked, or whether they're really endorsed by H.R., since they're reported by candidates and not confirmed by the companies in question. (We sent emails to the companies above; they either didn't respond immediately or declined to comment.) But Glassdoor says it creates its list by taking the half million questions contributed to its site over the past 12 months and pulling out a few thousand that were tagged with phrases like "brainteaser" or showed up less often, calling out the quirkiest for the list.
Susan Underwood, Glassdoor's head of global recruiting and talent acquisition, says that such questions, at least anecdotally, remain fairly typical: "As long as the question is value-based and the interviewer knows why they’re asking it, it can be valuable to understanding the candidate."
But at least one company often associated with brainteaser questions has said it's moving away from them. Glassdoor's list has been said in the past "to reflect the Google-ization of the interview process," referring to stories about the search engine's difficult interview questions. The tech giant once took out a billboard with a cryptic math puzzle on it; the curious computer scientists who solved it were sent to a web site with another challenging puzzle they had to answer before finally getting an email address to send in their resume.
Now, however, Google actually urges its hiring managers not to use such questions, according to a book released last year, "Work Rules," by Google's head of "people operations," Laszlo Bock. In it, he writes that they aren't actually worth much.
How a candidate performs on such questions "is at best a discrete skill that can be improved by practice, eliminating their utility for assessing candidates," he writes. "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 or self-satisfied. They have little if any ability to predict how candidates will perform in a job."
Bock admits in his book that some questions like this have been used at Google, and may continue to be, though he says that "we do everything we can to discourage this, as it's really just a waste of everyone's time." When they do pop up, he writes, senior leaders "ignore the answers to these questions."
Instead, Google now bases its interview process on assessment methods that research has shown to be most predictive of performance, Bock writes. Technical hires go through some kind of test of their ability to do things like write code or design algorithms. And then the company asks "behavioral" ("tell me about a time when...") or "situational" ("what would you do if...") structured interview questions that help assess things like a candidate's cognitive ability or conscientiousness.
"Yes, these questions are bland; it's the answers that are compelling," he writes.
As a result, it might be smarter to study up on a few of Glassdoor's most common interview questions -- yet another list it compiles -- than to try and rehearse answers for puzzling oddball questions. These include standard fare queries like those about strengths and weaknesses, as well as less obvious but still common questions, such as "How would you fire someone?"
Still, many companies or CEOs continue to put their own spin on the interview process. Charles Schwab CEO Walt Bettinger told the New York Times that he sometimes meets job candidates for breakfast and asks the restaurant to screw up the candidate's order, just to see how he or she treats the waiter. One of Warby Parker's founders told Quartz in 2013 that the company asks candidates about the most recent costume they wore to find people who are a good cultural fit.
And Facebook's global head of recruiting told Business Insider her favorite interview question isn't a tricky engineering one, but a query about what someone did on their very best day at work. "The question was conceived to help hiring managers assess someone's innate passion," wrote the Post's Peter Holley about Facebook's question. "But authentic passion, perhaps more than other qualifications, is hard to fake."
Just in case, what -- pray tell -- might be a good answer to the question about finding a penguin in the freezer? A Trader Joe's spokesperson declined to comment. But there was one response offered in the comments where the question was listed on Glassdoor, where users can weigh in with responses: "Only correct answer: Call animal control. This shows responsibility and respect for the animal and fellow co-workers."
UPDATE: After this article was published, a Delta spokesperson emailed to say the basketball query is not a standardized question.