Snapchat co-founder Evan Spiegel appeared relaxed as he addressed an over-capacity crowd of hundreds of University of Southern California students Wednesday, chatting with a leg crossed over his knee and bowing his head modestly at many of the university's introductions. "Hi guys, hey," he said with a grin. 

Smiling wryly as he was introduced as a Stanford University graduate, Spiegel shook his head. "I almost got a degree," he said with a laugh. "Stanford wants to make sure I'm very clear about that." 

The 24-year-old, asked to dispense advice to budding entrepreneurs at the Viterbi School of Engineering event, attributed much of Snapchat's success to its simplicity. "I think it was fun, you know?" he said. "We talk a lot about the way social media's changed. Social media was about identity. Building a virtual Evan. Here's what Evan likes. Here's pictures of Evan. That just gets really boring at some point."

Condensing the power of instant messaging was key, said Spiegel, in a social networking composition that had become tedious. "You end up with this huge accumulation of things that don't really reflect who you are at all. We care more about the essence of conversation," he said. "We focus on the feeling."

It was by virtue of this concentration, said Spiegel, who called snaps "little windows into somebody else's perspective," that allowed the company to bolster a brand. "I think people can take it pretty far. You notice we don't send text messages, we don't send emails."

Other seemingly minute differences, such as ensuring users' snap stories would play in the order they were captured, were what gave Snapchat a decidedly competitive edge, argued the CEO. "We're different from social media today, where everything is in reverse chronological order."

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Just days before, it was announced that the company could be valued by as much as $19 billion, close to double its value of $10 billion last year.

Spiegel described the app as a reminder of the commonality of communication. "The place we really started growing first was Norway," he said incredulously. "The way that they used it is really not that different... It's nice to remember that there's this common tie of communication that ties everyone together."

A central way Snapchat taps into consumer insight is by exercising the team's communication and empathy skills, added Spiegel. "We spend a lot of time actually listening to how people feel," he said. "I think that really is the core of what design is."

Every week, for instance, the company of more than 200 engages in what it calls "practice counsel," dispersing into groups of 10. "Everyone listens to how everyone feels," Spiegel said. "We kind of break up listening into two parts, because it's challenging."

Asked how the creative process might differ in L.A., Spiegel replied, "I absolutely think that people think big in Los Angeles. This city is known for that over a very long period of time."

"I remember what it was like when there were six or seven of us sitting in the beach house," continued Spiegel, who was raised in the Pacific Palisades. "Which was awesome, I'd recommend it. At that point, we really had to make the decision to stay."

While Snapchat did have access to capital in the Bay Area, the obvious dampener was a lack of local financing. The company discussed how to bring to L.A. "that kind of capital only found in entertainment," said Spiegel.

Staying competitive also requires the ability to "get very good at saying no," said Spiegel, who in 2013 famously surprised pundits by rejecting Facebook's acquisition offer for $3 billion. "And that's kind of like a rude thing, you feel bad... To get really good at that helps you stay focused."

At the same time, the co-founder singled out recognizing humility and accountability as one of his greatest leadership lessons. “Oh, God. You know I think we learned a couple times, I personally in particular learned the importance of saying sorry quickly,” he said. "I think my biggest failure was not saying sorry more quickly or appropriately as we screw up."

What people may not realize is that in the rush to get things out online, "we made a ton of mistakes," said Spiegel. "A ton, a ton. But we wouldn't do it differently, because we learned from those mistakes."

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In its nearly four-year span, the app has undergone a considerable evolution. The concept of stories was generated largely by user feedback on how to mass-message friends pictures, said Spiegel. "We probably got that question a billion times a day, for like a year... So we really had to look at that."

Last month, Snapchat introduced Discover, a mobile advertising feature that allows users to tap content from a selection of media companies. The CEO described the initiative as "giving a voice back" to the editorial perspective, while filling a visual gap lacked by other platforms like Twitter. "We believe it's really valuable to have someone who's smarter than us figure out what's important, because that's a full-time job, and a really hard one," he said. 

Hours before Spiegel's visit to USC, the company also rolled out a new feature that would allow music to be played while filming Snap videos. The app is seeking to better integrate music in general, said the CEO. "After communication, it's the highest frequency behavior on your phone, and so that makes it a really interesting opportunity." 

"I'm sure you get asked this question a lot," said Professor Soni, who took a selection of text messaged questions from the audience. "What's the secret to your success?"

"I thought you were gonna say, 'Do the photos really disappear?'" joked Spiegel. "They do."

Told that the audience had messaged in more than 100 questions, Spiegel smiled. "I'd just be sitting in the back sending Emojis."

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