NASCAR star Martin Truex Jr., 38, was frugal with his early earnings.
"I can remember when I was younger, I would get paychecks and I would kind of like let them stack up in my drawer," Truex tells CNBC Make It. "I was so proud of them, I didn't even want to cash them or put them in the bank."
While he was a super-saver, he admits now that it wasn't the best strategy.
"My biggest mistake was holding on to them too long, because I was losing out on interest," Truex says, referring to the money he could have made if he had invested his earnings.
"But aside from that, it's been pretty smooth ever since."
Indeed, Forbes reports Truex — who currently races for Furniture Row Racing — as earning $9.9 million, making him the 11th highest-paid NASCAR driver.
You can watch Busch, Logano, Harvick and Truex compete in the NASCAR Championship Sunday, Nov. 18, at 3 p.m. ET on NBC.
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