The CEO of a $2.8 billion startup says his favorite interview question is something we've all been answering since we were kids

SlackStewart Butterfield, the cofounder and chief executive of Slack.

When you interview with the CEO of a company, you never know what you're going to get. Some ask insanely difficult questions, while others stick to the more conventional "biggest strengths and weaknesses"-type queries.

Stewart Butterfield, the cofounder of Flickr and chief executive of Slack, perhaps one of the fastest-growing business apps of all time, asks job candidates a more familiar question - one we've been answering for our teachers and parents since we were kids.

In a recent interview with Adam Bryant of The New York Times, Butterfield said always asks: "What do you want to be when you grow up?"

"Good answers are usually about areas in which they want to grow, things they want to learn, things that they feel like they haven't had a chance to accomplish yet but want to accomplish," Butterfield said. "A very short answer to that question would be automatically bad."

He told Bryant that he used to ask job candidates one math question (what's three times seventeen?), one geography question (can you name three countries in Africa?), and one history question (what century was the French Revolution in, give or take 200 years?). "I didn't expect people to get the answers right, but I just want them to be curious about the world," he said. But he now sticks to the more telling "when you grow up" question.

Read the full New York Times interview here.

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