Before Dr. Laurie Santos became the instructor behind Yale's most popular course, a viral TED Talk speaker and a popular podcast host, she was a nervous college freshman getting ready to present her work for the first time.

"I remember just getting totally tongue-tied," Santos, who says online versions of her Yale course have reached 3.3 million people to date, tells CNBC Make It. "I felt like my heart was going to pop out of my chest."

Her saving grace: A pizza delivery arrived just as she was getting started, which gave her enough time to calm her nerves and gather her thoughts.

At the time, Santos considered the experience a major failure, but now she credits her public speaking success to those freshman-year jitters. Now, when she gets anxious right before an event, she knows she'll get through it. It can't be much worse than a full body panic — and even if it is, she's been there before.

"I really had to fail to learn that I was resilient enough, that I could make it through a nerve-wracking experience and get to the other side," Santos says.

Santos wants everyone to rethink failure, given the benefits she's seen in her own life.

"We forget failure really is a path to success," she says. "We need to have much more of a growth mindset about failure."

Coined by psychologist Carol Dweck, a growth mindset is when you believe you can always improve and learn more, even when it comes to your greatest strengths. The flip side: a fixed mindset, or the belief that your skills and talents can't change over time.

People with growth mindsets tend to learn more from their failures, research shows. It's no reason to actively seek out failure — but viewing your frustrations as learning opportunities can help you find silver linings in those moments.

That's easier said than done, of course. You may need to do some introspection and self-analysis to figure out why a particular failure bothers you so much, so you can find a way to move forward from it, as psychologist Dr. Jenny Wang wrote for CNBC Make It last year. 

In Santos' case, once she realized how much she stood to learn from her public speaking jitters, she started using that initial feeling of failure as a pep talk before other presentations.

"Those nerves are good," Santos says she tells herself. "They're just a sign that you're going to get better."

The simple reminder is both calming and motivating, she says — a concrete way of dealing with the nervousness she still occasionally feels while speaking to a crowd.

It's her goal for any failure: Learn and grow enough from it that you won't make the same mistake twice.

"One of the best ways of doing that — of getting better over time — is to actually experience failure, to experience the consequences of messing up," Santos says. "That allows us to learn more about how to do better in the future."

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