It's your worst nightmare: You're on a job interview, they ask you a question and you don't know the answer. Your heart races. Beads of sweat begin to form. C'mon, don't blow it — THINK!
Fun as it is to just show up and panic, it's better to be prepared for the worst. Well, job site Glassdoor.com is out with their annual list of the Top 25 most difficult companies to interview with.
It's like having an older brother who gives you pointers on what to expect from Miss Renkins' calculus exam.
If this isn't your first time at the hard interview rodeo,you probably know that consulting firms are notorious for their tough interviews. In fact, they've got a lock on three of the five top spots this year—McKinsey & Co. (No. 1 for a third year in a row), Boston Consulting Group (No. 3) and Bain & Co. (No. 5).
(Read more: The 10 least stressful jobs for 2013)
"The goal of our interview process is to mimic in a controlled setting of what it's like to engage on an actual client engagement," said Keith Bevans, the head of Bain's Global Consultant Recruiting Team. "The goal is to have a business discussion—not administer a quiz or final exam."
There are also a lot of big tech names on the list,including Google (No. 8), Microsoft (No. 16) and Facebook (No. 22). And, some big blue chips such as household-products giant Procter & Gamble (No. 14) and heavy machinery maker Caterpillar (No. 24).
There are a few names you might not expect, including Rolls-Royce (No. 6), business-card maker Vistaprint (No. 12) and educational non-profit Teach for America (No. 13).
Surprisingly, there weren't many financial-services companies on the list, but one that made it was BlackRock (No. 17).
"Failed an interview the first time I applied, passed the second time," one candidate for an analyst position said. "As a person with a non-finance and non-programming background, I had questions ranging from general knowledge to puzzles to project management to my extra-curricular interests in coding."
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A candidate interviewing for a product-manager job at Facebook was asked: "Where do you see the future of Facebook?"
The candidate said after delivering a few ideas, the response from the interviewer was: That's not that different from what we have now. "It was," the candidate said, "but she was apparently expecting more than my already unconventional ideas."
That person did not get the job.
One of the questions asked at an interview for a business-analyst job at Bain was: "Try to estimate the revenue from sale of tickets at Olympics 2012."
*Gulp* How do you answer that?
After you're done swallowing your tongue, the first thing you should remember is: There is no right answer. It's about seeing how you go about solving a problem—a problem you could easily encounter if they hire you.
Often, Bevans said, these "hypothetical questions" are actually based on real issues that came up with clients. In the case of the Olympics question, the company might be looking at investing in a company that does business with the Olympics.
According to Bevans, there are two important things they're looking for in your answer to a question like that: 1) How comfortable you are with numbers and 2) real-world orientation. If you blurt out: "100 million!," that would show a comfort with numbers—but no real-world orientation.
"Wait, you're assuming one in every three people in the country is going to go?!" Bevans said. (The U.S. population is around 313.9 million.)
Here are two possible ways you might approach that question, he said: 1) You might say, "I'll assume X percent of the population in the country tries to makes it" then multiply by an estimated ticket price or 2) "I read an article that there are 10 stadiums with an average capacity of 30,000. Assuming the Olympics sell out every day and the games run for 10 days, I'd estimate the revenue at X."
"It's not about the answer—but how you think about structuring it," Bevans said.
He added that Bain is very team-oriented so in the real world, the answer to this question from one associate would never be assumed as fact and immediately sent to the client. Rather, a team member would crunch some numbers, bring it to a team meeting, kick it around, etc.
Among the other tough interview questions job candidates reported:
"If I took your resume and removed the name at the top, what line on your resume would make your friends read it and recognize you?"
- interview at Boston Consulting Group for a consultant job
"How would you build an engine from scratch?"
- interview at Rolls-Royce for an engineer job
"How many people watched YouTube in my country in the last hour?"
- interview at Google for search-quality analyst job
"What kind of people do you dislike the most?"
- interview at health-care products maker Stryker for a sales rep job
"Teach me something."
- interview at computer-software maker Hubspot for a marketing-consultant job
"Name as many uses for a brick as you can in one minute."
– interview at graphics-chip maker Nvidia for a campaign-manager job
Of course, a lot of these tough questions tend to be for analyst and engineer jobs but Bevans said they apply similar approaches to hiring for other positions—everyone from the IT staff to the administrative assistants. What they're getting at is finding out how you approach real-world problems.
For the IT guy, they might ask: "My computer has these problems—how would you go about diagnosing it?" The answer isn't just about the ability to problem solve—it's how they would handle the customer, Bevans said.
(Read more: Most outrageous interview questions)
For the admin staff, they might ask: "Here's a travel situation that came up. How would you approach it?"
The interview process at Bain tends to take a couple of days and generally involves a written component. What that helps with is people who have great analytical skill—but maybe not the most polished, dynamic in-person presentation.
The interview process at some companies can take more than a month.
Candidates applying for jobs at ThoughtWorks and Vistaprint said they sat for seven interviews. At Avaya, it was eight—and it took six hours!
Overall, the companies with the longest interview process were Teach for America, Procter & Gamble and Rolls-Royce, ranging from 46 to 55 days.
And, while you might think the business of toothpaste, paper towels and diapers is, um, a piece of cake, one candidate said the interview at Procter & Gamble was very thorough.
"Really it's a company with strong values and they are looking for people with good personalities and character. So their interview process is all about filtering people through to see who can drive results, who can have fun, and who is competent enough to compete within," the candidate, who was interviewing for a process engineer job, said. "[J]ust trying to see if somehow you slipped through the cracks!" the candidate said.
The company that had the most negative reviews of the interview process was online-payroll firm Paycom, with 52 percent of job candidates reporting a bad experience. By contrast, the average on Glassdoor for bad experiences is 13 percent.
Rolls-Royce and Avaya had the most positive job-interview experiences reported, with 86 percent of candidates saying they had a good experience. That compares to the average of 52 percent across all companies on Glassdoor.
The companies with the highest employee satisfaction rate were Facebook, computer software firm Guidewire and Bain & Co.
And, while you might think a tough job interview is going to make you sweat bullets, it's important for job candidates to not walk into an interview on the defensive, feeling like they're about to be interrogated by a firing squad.
"Interviewers always want to see you do well. No one is out to get you! We want to grow as a firm and we need all the qualified people we can get," Bevans said. It's about a candidate's ability to engage and kick the ball around a bit with the interviewer, in the same way they would their future colleagues.
"We want candidates to walk out of the interview feeling like, 'Wow. I just had a really interesting business discussion.'"
Here's the full list of the Top 25 Most Difficult Companiesto Interview 2013:
1. McKinsey & Co.
3. Boston Consulting Group
5. Bain & Co.
7. ZS Associates
13. Teach for America
14. Procter & Gamble
Rolls-Royce no longer makes luxury cars — RR cars are made by BMW. Rolls-Royce is a power-systems manufacturer for the aerospace, energy and marine industries.