I’m taking some time off. So instead of doing new interviews, I’m looking back on a few of my old ones and pulling a big idea from each. — Andrew

Founders I interview keep telling me to focus on the One Thing, the key feature that’s so important to users that they’d put up with the bugs which are a natural part of a startup’s early days, but I often wonder, “how can we find that One Thing?”

So when I interviewed David Cohen, TechStar‘s founder, I asked him about it. He told me to try making customers scream, when they do, you know you’ve got it.

He told me the story of Darren Crystal, the co-founder of Photobucket who noticed that a lot of his users where uploading photos to his site and then embedding those photos on other sites, which wasn’t what Photobucket was originally built for.

His response was to say, “Let’s not let them do that,” and he disabled embedding. That’s when users screamed.

The anger led to the company’s big discovery.

That’s when he said, “let’s make that even easier.” At that point, Photobucket discovered the core feature that gave it its identity and eventually helped lead it to a $250 million acquisition.