Here's how the head of HBO documentaries decides which projects get made

For over 30 years, HBO Documentary Films president Sheila Nevins has found compelling ways to make us want to watch non-fiction films.

Though documentaries are more popular than ever, the way Nevins finds the stories hasn't changed much over the years.

She still searches through The New York Times for stories that need deeper exploration, her team brings her ideas, and filmmakers with a relationship at HBO pitch her.

She recently told Business Insider that what makes the best films are the ones "you're just busting with a desire to tell a story and find out more about it."

When BI spoke with Nevins the day after the Amktrak crash in Philadelphia, she didn't see a story there to tell as an HBO doc. However, something like law enforcement's handling of the capture of those responsible for the Boston Marathon bombing still fascinates her.

"That's what makes the job so interesting," said Nevins. "It's always different."

"I'm a great believer in the anonymity of the documentary subject," she added. "I think the stories of ordinary people are much more interesting because they are extraordinary. Fame tends to repeat itself. Someone's famous because they wear certain clothing or are famous because they've been in something or famous because of their political views. They just kind of regurgitate the same philosophy. It's interesting, but it doesn't require discovery in the same way that anonymity does."

For the latest HBO documentary, "Requiem for the Dead: American Spring 2014" (airing June 22), the idea in how to tell the story of gun violence in America was very different. The film's directors Shari Cookson and Nick Doob told Nevins they wanted to make the whole film out of the social media posts the victims made before they died. Nevins said yes without hesitation. ?

"There's not one bit of original filming in it," said Nevins of the film. "So it's America on its own without any creative engagement. I think it's one of the best documentaries we've done."

But there are some projects Nevins passed on that still keep her up at night. Particularly the 2011 Oscar-nominated "Restrepo," which looked at a year in the life of a platoon stationed in one of the most deadly locations in Afghanistan.

"'Restrepo' eats away at me," said Nevins. "It pissed me off that I didn't see it as being successful. I was more careful the next time about choosing a war story."

That next time would be her executive producing the documentary short "Crisis Hotline: Veterans Press 1," which looks at a unique service that supports the traumas our military veterans suffer.

The film won best documentary short at this year's Academy Awards.