It's a particularly busy week for me: on top of a few looming deadlines, I'll be at Business of Software 2008 in Boston. So, I figured it'd be the perfect opportunity to revisit some classics.

Job Interview 2.0: Now With Riddles! was originally published on May 15th, 2007, and is one of my personal favorites.

Some years ago, someone at Microsoft noticed that they were having a bit of a Resources problem. A Human Resources problem to be specific. There were a whole lot of job openings (thousands, in fact) and a whole lot of applications (hundreds of thousands, in fact), and no easy way to match the right applicants with the right jobs. So they decided to reinvent the Job Interview.

Traditionally, job interviews are used to ascertain two things: how competent the candidate is and how well his personality (or lack thereof) will fit in with the organization. With their introduction of Job Interview 2.0, Microsoft included both of those features and added one additional: how the candidate responds when presented with asinine, utterly pointless, and completely ridiculous brainteaser questions.

Of course, common sense tells us that a candidate who enjoys solving silly riddles would most likely enjoy solving a silly riddle at a job interview. The same can be said about pepperoni pizza: chances are, if a candidate enjoys eating pepperoni pizza, he will also enjoy eating pepperoni pizza at a job interview. Both are facts which, while completely enthralling (no way, you like pepperoni pizza, too?!), are equally as irrelevant when determining whether someone would make a good programmer.

If you haven’t seen any of the Job Interview 2.0 questions offered by Microsoft, here are a few:

  • How would you determine the weight of a Boeing 747?
  • Given an opaque box with three light bulbs inside and three switches outside, how would you determine which switch corresponded to which bulb if the box could be opened only once and only after all the switches were permanently set?
  • You are at a ravine with three others and need to cross a rickety bridge. You can cross it in one minute, the three others can cross it in two, five, and ten, respectively. A flashlight (your group has only one) is always required to cross, and only two people can cross at a time. How do cross as quickly as possible?

Naturally, being that they’re brainteasers, no common sense or practicality is allowed. And this is precisely why I would fail miserably at this part of Job Interview 2.0:

  • I’d ask Boeing… I can’t ask Boeing?! Uhh, I’d ask a librarian… Of course a librarian would know, they look stuff up, that’s their job!
  • Who would build such a stupid, broken box? I’d fix it of course… I haven’t even seen the stupid box! How do you know I can’t fix it?
  • Obviously, we’d leave the slow guy behind. We’re clearly in a bad place, in a bad situation, and we don’t have any time for the big fat fatty to slow us down. It’s survival!

Thankfully, Microsoft realized that the type of people who enjoy these riddles aren’t always good programmers, and good programmers aren’t always the type who enjoy these riddles. In fact, some of the folks who can solve these riddles are precisely the type of people you don’t want as programmers. Would you want to work with the guy who builds a water-displacement scale/barge, taxis a 747 to the docks, and then weights the jumbo jet using that, instead of simply calling Boeing in the first place?

Unfortunately, Microsoft’s realization came too late: a whole mini-industry has spawned around the concept of Job Interview 2.0. If Microsoft did it, it must work, right? There are books written on brainteasers in the interview, consultants who will help your company annoy the hell out candidates with your very own custom brainteasers, and now, everyone from small software firms to big ole’ banks are asking stupid riddle questions.

They will eventually realize how useless of a practice this is. They will eventually give it up. In the meantime, however, you – the job seeker – will have to put up with it.

Or not. One reader shared with me the story of his brainteaser interview.

During a screening interview, I was asked how I would design a bike fit for someone visually impaired. I responded something to the effect of, "What, like, for blind people?", and she answered yes.

I thought for a moment and then I responded, "Well.. a blind person riding a bike doesn't sound like a very safe idea, so I would make the bike stationary, maybe with a fan blowing in the person's face. He probably wouldn't even know the difference."

She was speechless.

Now, granted, he will not get the job. Despite the complete absurdity of the design request, and the complete practicality of his answer, the job will go to a candidate who manages to answer the question by designing an extremely overcomplicated solution for a completely non-existent problem. And that candidate will be the same person who designs their software.