One candidate was silent for a long moment, then tried, "Well, I drove here last night with my boyfriend to make sure I didn't get lost today."
Another replied, "I read your Wikipedia."
Both answers were better than nothing, but hardly enough to demonstrate the kind of passion and curiosity and, most importantly, the resourcefulness I was looking for.
Look, there are plenty of great interview questions out there. And there's no doubt about it — if you're a hiring manager, you need to ask a slew of them, as well as carefully check references. (I also give candidates a good, old-fashioned editing test.) But this single query has proven its worth to me time and again.
Half the battle in business is being prepared. If you're asking the questions in an interview, make sure the people you hire don't have to learn that on the job. And if you're answering them, prove you already know it.
Suzy Welch is a CNBC contributor and the author of several best-selling business books, including "10-10-10: A Life Transforming Idea," "The Real Life MBA" and "Winning."