For the more neurotic among us, a birthday can be a reminder of how another year has passed and our loftiest aspirations have faded further into the distance.
There are plenty of examples, however, of successful people across many industries who prove that you don't need to have it all figured out by the time you turn 30.
We'll take a look at some of them, from renowned fashion designer Vera Wang, who didn't design her first dress until she was 40, to writer Harry Bernstein, who authored countless rejected books before getting his first hit at age 96.
Get inspired by those who show it's never too late:
Stan Lee created his first hit comic, "The Fantastic Four," just shy of his 39th birthday in 1961. In the next few years, he created the legendary Marvel Universe, whose characters such as Spider-Man and the X-Men became American cultural icons.
Donald Fisher was 40 and had no experience in retail when he and his wife, Doris, opened the first Gap store in San Francisco in 1969. The Gap's clothes quickly became fashionable, and today the company is one of the world's largest clothing chains.
Vera Wang was a figure skater and journalist before entering the fashion industry at age 40. Today she's one of the world's premier women's designers.
Gary Heavin was 40 when he opened the first Curves fitness center in 1992, which ended up becoming one of the fastest-growing franchises of the '90s.
Robin Chase cofounded Zipcar at age 42 in 2000. She left the company in 2011 and continues to build and advise startups, as well as serve as a member of the World Economic Forum.
Samuel L. Jackson has been a Hollywood staple for years now, but he'd had only bit parts before landing an award-winning role at age 43 in Spike Lee's film "Jungle Fever" in 1991.
Sam Walton had a fairly successful retail-management career in his 20s and 30s, but his path to astronomical success began at age 44, when he founded the first Wal-Mart in Rogers, Arkansas, in 1962.
Henry Ford was 45 when he created the revolutionary Model T car in 1908.
Jack Weil was 45 when he founded what became the most popular cowboy-wear brand, Rockmount Ranch Wear. He remained its CEO until he died at the ripe old age of 107 in 2008.
Rodney Dangerfield is remembered as a legendary comedian, but he didn't catch a break until he made a hit appearance on "The Ed Sullivan Show" at age 46.
Momofuku Ando cemented his spot in junk-food history when he invented instant ramen at age 48 in 1958.
Charles Darwin spent most of his life as a naturalist who kept to himself, but in 1859 at age 50 his "On the Origin of Species" changed the scientific community forever.
Julia Child worked in advertising and media before writing her first cookbook when she was 50, launching her career as a celebrity chef in 1961.
Jack Cover worked as a scientist for institutions including NASA and IBM before he became a successful entrepreneur at 50 for inventing the Taser stun gun in 1970.
Betty White is one of the most award-winning comedic actresses in history, but she didn't become an icon until she joined the cast of "The Mary Tyler Moore Show" in 1973 at age 51
Tim and Nina Zagat were both 51-year-old lawyers when they published their first collection of restaurant reviews under the Zagat name in 1979. It eventually became a mark of culinary authority.
Taikichiro Mori was an academic who became a real-estate investor at age 51 when he founded Mori Building Company. His brilliant investments made him the richest man in the world in 1992, when he had a net worth of $13 billion.
Ray Kroc spent his career as a milkshake-device salesman before buying McDonald's at age 52 in 1954. He grew it into the world's biggest fast-food franchise.
Wally Blume had a long career in the dairy business before starting his own ice cream company, Denali Flavors, at age 57 in 1995. The company reported revenue of $80 million in 2009.
Laura Ingalls Wilder spent her later years writing semi-autobiographical stories using her educated daughter, Rose, as an editor. She published the first in the "Little House" books at age 65 in 1932. They soon became children's literary classics and the basis for the TV show "Little House on the Prairie."
Harland Sanders, better known as Colonel Sanders, was 62 when he franchised Kentucky Fried Chicken in 1952. He sold the franchise business for $2 million 12 years later.
Anna Mary Robertson Moses, better known as Grandma Moses, began her prolific painting career at 78. In 2006, one of her paintings sold for $1.2 million.
Harry Bernstein spent a long life writing in obscurity but finally achieved fame at age 96 for his 2007 memoir, "The Invisible Wall: A Love Story That Broke Barriers."
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