Photograph by Benjamin Rasmussen for Fortune
“You don’t fail until you stop trying.” –Charles Falzone [her father]
Debbie Sterling, 32
Founder and CEO, GoldieBlox
Photograph by Laura A. Oda — AP
“I had a painting teacher, Kevin Bean, who told us to ‘kill all your darlings.’ Sometimes we get too focused on one small thing that you just love, and ignore the rest of your canvas in favor of what is essentially a fairly insignificant piece with a lot of emotional attachment. Kevin encouraged us to paint over that one thing and free ourselves to see the bigger picture. In business, I’ve found that it is important to stay nimble and pivot when necessary – not every piece of every idea is going to be brilliant or even make sense. It can be really hard to see everything that is going on or change directions if you’re bogged down in the nitty-gritty details.”
Michael Dubin, 37
Co-founder and CEO, Dollar Shave Club
Photograph by Michael Lewis for Fortune
“You have to create the quiet to be able to listen to the very faint voice of your intuition.” —Jon Favreau
James Park, 39
Co-founder and CEO, Fitbit
Photograph by Benjamin Rasmussen
“During my first startup, a VC told me to spend cash as fast as we could to grow.
We took that advice, and the company ultimately went under during the dotcom collapse because we ran out of cash. The advice was terrible in the short term, but it did teach me the importance of good cash management and the importance of driving profitability.
Both of those things served Fitbit really well, given the capital challenges of building a connected hardware company. In a lot of respects, weirdly enough, that was the best piece of advice I’ve ever gotten.”
Logan Green, 31
Co-founder and CEO, Lyft
Photograph by David Paul Morris — Bloomberg via Getty Images
“Focus on one thing, and do that really, really well.”
—Sean Aggarwal, Lyft’s first investor
Yehuda Shmidman, 34
CEO, Sequiential Brands
Photograph by Peter Foley—Bloomberg via Getty Images
“An executive I met along the way once said, ‘Don’t confuse activity with progress.’ Brilliant—especially in today’s world of being constantly over-inundated by emails, texts, and phone calls.”
Kayvon Beykpour, 26
Co-founder and CEO, Periscope
Photograph by Noam Galai—Getty Images
“ ‘There are a few people who will change your life forever. Find those people.’ Not sure [about] the exact origin, but I saw this written recently, and it’s similar to something my dad shared with me when I was much younger. It stuck, and means a lot to me.”
Sam Altman, 30
President, Y Combinator
Photograph by David Paul Morris — Bloomberg via Getty Images
“Make something people want.” —Paul Graham
Reshma Saujani, 39
Founder and CEO, Girls Who Code
Photograph by Monica Schipper — Getty Images
“ ‘Fail hard, fail fast, fail often. It’s the key to success.’ This one I learned from experience!”
Trevor Nelson, 37
Co-president and Managing Partner, Alliance Consumer Growth
Co-president and Managing Partner, Alliance Consumer Growth
Courtesy of Alliance Consumers
“‘Learn to court measured risk.’ My high school English teacher told me that.
Ashifi Gogo, 34
Ashifi Gogo, 34
Co-founder and CEO, Sproxil
Co-founder and CEO, Sproxil
Courtesy of Sproxil
Courtesy of Sproxil
Courtesy of Sproxil
“It came from a ridiculously challenging graduate engineering test that could only be solved by approximation: Many problems can be solved approximately right.”
Taylor Swift, 25
Entertainer
Photograph by George Pimentel—LP5/Getty Images
“I think the best advice that I ever got as a teenager was to think about your actions.
Because if you are 80 years old looking back, you know if your dad calls you at eight in the morning and wants to go to breakfast, as a teenager you are like, ‘No, I want to sleep,’ and as an 80-year-old looking back, you go to breakfast with your dad. It’s just those little decisions like that.”
—As said at the 2011 Teen Choice Awards
Productivity hack
Apoorva Mehta, 29
Founder and CEO, Instacart
Photograph by Benjamin Rasmussen for Fortune
“Taking one mandatory day off every week has done wonders for my productivity. I realized a few years back that I used to burn out every few months, and it was happening increasingly. By taking one full day off, I was able to give my body and brain a much-needed break that allowed me to come back to work refreshed.”
Melanie Whelan, 38
Melanie Whelan, 38
CEO, SoulCycle
CEO, SoulCycle
Courtesy of SoulCycle
Courtesy of SoulCycle
“Prioritize. Figure out the few key things that are most important in your role for you to have an impact on your business. Make these things your sole priorities. It’s really easy to fill your time with email and meetings—ultimately this can just be busywork. When you set your priorities on the things that will move the business, your team, or your department forward, you’re going to have an impact.”
Ashifi Gogo, 34
CEO, Sproxil
“Avoid bad meetings and the tempting In-Box Zero. Skip email on occasion, pick up the phone, and have a wonderful conversation from time to time. Memories count.”
Parker Conrad, 35
Co-founder and CEO, Zenefits
David Paul Morris/Bloomberg—Getty Images
“Start drinking coffee—or up your dosage. I was never a coffee drinker until I started Zenefits. Those first six months were the most productive of my life.”
Anand Swaminathan, 39
Managing Director, Accenture Digital
Courtesy of Accenture
“Work hard, but play harder. If you work really hard, you have to play harder to keep your mental fitness.”
Ryan Graves, 32
SVP of Global Operations, Uber
SVP of Global Operations, Uber
Courtesy of Uber
Courtesy of Uber
“Don’t take life too seriously, you’ll never get out alive. Not sure where I got this, but reminding myself of this fairly often allows me to manage okay with a lot on my plate.”
Stacy Brown-Philpot, 39
COO, TaskRabbit
Photo: Courtesy of Task Rabbit
“Relationships matter.”
—Sheryl Sandberg
On leading
“It came from a ridiculously challenging graduate engineering test that could only be solved by approximation: Many problems can be solved approximately right.”
Andy Katz-Mayfield, 33
Co-founder and co-CEO, Harry’s
Courtesy of Harry’s
“You have to recognize that every out-front maneuver you make is going to be uncomfortable. That warm sense of everything going well is usually the body temperature at the center of the herd.”
—Irv Grousbeck, professor, Stanford Graduate School of Business
Brian Sheth, 39
Co-founder and President, Vista Equity Partners
Courtesy of Vista Equity Partners
“You aren’t going to save the world on your own. But you might inspire a generation of kids to save it for all of us. You would be amazed at what inspired children can do.”
—Dr Jane Goodall, explaining to me why she started Roots and Shoots
Jessica Alba, 34
Founder, The Honest Company
Photograph by Jessica Sample—The Honest Company
“Never allow a person to tell you no who doesn’t have the power to say yes.”
—Eleanor Roosevelt
Advice from mom and dad
Ryan Graves, 32
“You become the company you keep. I originally got that from my parents, and the theme has definitely played out in life.”
Vas Narasimhan, 39
Global Head of Development, Novartis Pharmaceuticals
Courtesy of Novartis
“The best advice came from my father, who has always told me to focus on how you live and how you impact the world, and the rest will take care of itself.”
Ronda Rousey, 28
UFC fighter
Photograph by Jae C. Hong — AP
“I get asked that a lot and I always go back to my mom’s, ‘No one has the right to beat you.’ I take that to every venue that I’m in. She would say, ‘Someone has to be the best in the world, why not you?’ I always try to keep that in mind.”
Julian Steinberg, 36
Courtesy of Alliance Consumer
“My father’s motto was, ‘Always have the courage to persevere.’“
Noah Wintroub, 39
Vice Chairman, J.P. Morgan Chase
Courtesy of J.P. Morgan Chase
“From my mom: ‘Pick your battles wisely.’ From my grandma: ‘This too shall pass. Acknowledge your success and failures quickly and move on.’ And from my rabbi : ‘You’re only as successful as the least well-off person in your community.’”
Michelle Dipp, 39
Co-founder and CEO, OvaScience
Courtesy of Ovascience
“My mom has been a constant source of support and advice. One of her best is, ‘Be passionate about people.’”
Orion Hindawi, 35
Co-founder and CTO, Tanium
Photograph by David Paul Morris — Getty Images
“My father, David, told me something when I was 5 years old—he sleeps great at night because he is honest during the day.”
Jared Kushner, 34
CEO, Kushner Cos.
Courtesy of Kushner Cos.
“My father always told me, ‘Don’t waste energy worrying about things you can’t control. Spend your energy focusing on solutions.’”
“Growing up, my mother always told my sister and me that if we put our minds to it, we could do it. Whatever it was.”
To see the 40 Under 40 list, visit fortune.com/40-under-40.
A version of this article appears in the October 1, 2015 issue of Fortune magazine with the headline “The best advice I ever got.”
