At some point in life, everybody has to take a start on a new project, whether that's school, a hobby, or a new job or career. Everybody is a beginner at some point.
And the biggest mistake you can make is not seeking advice from the right sources.
That's according to Jim Wendler, a former college football player who turned to power-lifting and business. He squats over 1,000 pounds in competition, and his 5/3/1 program for weightlifting has been taught to millions of athletes around the country. His books have sold over 547,000 copies.
"I tell people all the time: The biggest problem with beginners is they listen to other beginners," Wendler tells CNBC.
"I always view it like this," he says. "For example, can you play the saxophone? No? Okay, I can't play the saxophone either, so imagine if we are teaching other how to play. It would sound like a mess."
Wendler pointed out other examples, too, like taking legal advice from somebody who's not a lawyer.
In Wendler's day job, he talks about all the people who told him he wasn't going to make it as a champion lifter, a coach, a trainer, an author, a person with his own brand that has resonated with so many people. They were "beginners" in those fields, and didn't know the first thing about what they were doing. Their advice shouldn't have mattered.
Likewise, when it comes to career moves, there are plenty of people out there who will tell you what they think, but how many of them really know what they're talking about?
If you're starting out, don't listen to your peers if they're beginners too. Seek out advice from the leaders in the field, the best people you can find. And perhaps from Wendler, who is not a beginner and who releases his latest book, "5/3/1 Forever," on March 24.