For Google veteran Susan Wojcicki, the company’s top woman executive and one of the most powerful people in the advertising business, moving over to YouTube earlier this year was something of a chance to hit the rewind button.

“It reminded me a lot of Google in 2003 or 2004, when we were a much smaller company,” Wojcicki said Tuesday during an on-stage interview at Fortune’s Most Powerful Women Summit in Laguna Nigel, California. “We had all these big plans but we didn’t have enough people to get them done.”

Her second go-around in the role of startup executive wasn’t exactly like the first, as YouTube, where she is CEO, is backed by the massive financial resources of its owner, Google GOOG . But with the online world video brimming with opportunities, figuring out what not to do is as hard as deciding what to do, said Wojcicki. Her advice? Pick a few things and do them well.

With 400 hours of video uploaded to YouTube every minute, the online video behemoth represents different things to different people. For Wojcicki, two main aspects – one that’s idealistic, one that’s all business – stand out.

YouTube, she said, “gives a voice to people who would otherwise not have a voice.” That ranges from people in Venezuela or Ukraine telling the rest of the world about their struggles, to gay and lesbian teens facing bullying and a rash of suicides rallying around the “It Gets Better” campaign.

“If you didn’t have a way to communicate across the globe,” Wojcicki said, “what would happen?” That aspect of YouTube as a global communications hub is “very important to me,” Wojcicki said.

That said, there’s little doubt that her tenure as YouTube CEO will be judged by her success growing the business side. In recent years, YouTube has emerged as the springboard for a new generation of digital video creators. Some have audiences that surpass those of popular cable programs.

Wojcicki said she first learned about that world through her children. “My son had 100 different channels he was following,” she said. “I had no idea. He knew everything about those 100 creators.”

Wojcicki talked about her efforts to make that burgeoning community of content more like television, by promoting some of them to a wider audience and helping to finance certain shows. “These YouTube personalities were well known to their audiences but not to other people,” she said.

At the same time, Wojcicki said, YouTube wants to preserve the things that make its platform unique. “This is a different medium,” she said. Creators are not hemmed in by a standard format. Shows, she said, “can be one minute or an hour so there is a lot more creative freedom.” What’s more, creators communicate directly with their audiences and incorporate input from their fans.

A key to success in that environment? “The next generation really expects the content to be authentic,” Wojcicki said.