This story is part of the Behind the Desk series, where CNBC Make It gets personal with successful business executives to find out everything from how they got to where they are to what makes them get out of bed in the morning to their daily routines.

For Jessica Alba, being famous and being successful are two wildly different concepts.

She's been balancing the pressures of both since her early teens. Alba began acting at age 13, rose to prominence at age 19 in the sci-fi TV series "Dark Angel" and shifted gears from Hollywood to launch The Honest Company, a nontoxic-household goods company, at age 29.

When she branched out into entrepreneurship, plenty of people questioned the choice — and few expected her to succeed. She founded Honest after becoming a new mom and realizing that many baby products contained harmful chemicals, she tells CNBC Make It. And Hollywood fame felt fleeting to her — like it could disappear at any moment.

"In entertainment, in particular, there's no amount of success that ever gives you a real foundation or a real place in this industry," Alba, 40, says.

But Honest hasn't been an easy ride, either: The business has been plagued with lawsuits for wrongly labeling ingredients, leadership shakeups and increased competition over the years. Alba says the company has learned from those challenges, and has "moved forward in the right way" — spending 2% of revenue annually on research and development and quality testing "to ensure we deliver safe and effective products that work."

In May 2021, just days after Alba's 40th birthday, Honest went public via IPO at $16 per share, giving the company a $1.4 billion valuation. Today, shares are trading near $6, and the company is valued at roughly $550 million.

Alba, who sits on the company's board and serves as its chief creative officer, is often seen as the public face of the company. In her early days, she says, she used her doubters to fuel a relentless work ethic.

"I put a lot of pressure on myself over the years," she says. "It kept me in this state, almost like a hamster wheel."

Now, she says, she has more self-worth and a better understanding of herself, which she credits to therapy. More importantly, she says, she finally feels secure — and passionate about her career, and the health and wellness-focused company she's built.

Here, Alba discusses why she works so hard to overcome expectations, the process of building Honest and why she wishes she'd started therapy sooner.

On where she gets her drive: 'There were no expectations for me to be successful'

I grew up in a very modest and pretty traditional Mexican-American family. It was very male-dominant and Catholic-dominant. Religious ideals about women's roles and men's roles and all of that. The world wasn't open, and the path wasn't paved.

It just felt so wrong to me.

In a way, there were no expectations for me to be successful at anything. But then, that left so much potential. Anything's better than nothing, right? You can't really fail if you try something. There's this innate kind of fearlessness that comes with starting from the bottom.

There's a video of me at Disneyland when I was like 6, saying, "I'm an independent woman. I'm never going to rely on a man." I've always had this energy to prove that women can be intelligent and equal. Women can excel in life, and should be treated with fairness.

Those rights are something we all should have, regardless of what culture or community you come from. So maybe that's my drive.

On deciding to launch a business outside of Hollywood: 'I was never that secure in my success'

Successful, for me, means: I don't have to live month to month. That was a stress and a burden that I lived with growing up, and when you're in survival mode, it's very difficult to have aspirations of the life that you dream of having.

Fame, which is a separate thing, is bizarre, weird and not normal. I never was comfortable with it. the entertainment industry is very quick to spit you out and decide that you're not relevant. We don't care. On to the next one.

For me, financial stability is a big piece of being able to know that you're going to be OK. I didn't trust it, actually, for a very long time.

On building Honest: 'It actually reminds me a lot of raising kids'

It actually reminds me a lot of raising kids: When you think you've got it figured out, a whole other thing [happens], and you're like, "Whoa, OK, here we go."

I had to release my need to control the process. I've learned a lot about the power of teamwork, and being able to support other people and the greater good — having the nugget of the idea and the vision be really clear, but [knowing that] how you get there is going to be different every time.

Naysayers or haters would energize me, in a way. Oh, you think I can't do it? Watch this. It gave me that fire to really keep going. But now, it doesn't really get to me the same way. It rolls off differently now.

Whatever people are going through in life — their life experiences and their trauma — they're projecting it onto other people. They're going to spew negativity, and that's fine, because it does something for them. But I don't need any of that. It has nothing to do with me.

So, I let that live over there for them. I'm going to just keep on keeping on over here.

The advice she would give her younger self: 'I would have started therapy earlier'

I would have started therapy earlier. Once you understand yourself, and why you do what you do, and how you operate in the world, it unlocks your potential. You may not even know you're doing certain things that keep you from happiness, self-worth or your goals.

I put a lot of pressure on myself over the years. It kept me in this state, almost like a hamster wheel. I [could] never really break through until I understood the core of why I felt that way, and where [it was] coming from.

I just had so much angst when I was 20 years old. It was so hard. It's so hard for young people because you don't have the tools. You don't have the life experience to know that time heals, and you'll figure it out.

Once you understand that you can break through, there are so many possibilities of how you can exist or live or walk through the world. It feels so much better now.

So, I probably would have worked on myself earlier. But it's almost like you need to go through [those struggles] to understand that it's not the thing to worry about. [As you get older], you definitely care less about what people think.

This interview has been edited for length and clarity.

Update: This story has been updated with comments from Alba about the challenges The Honest Company has faced since launching in 2011.

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