.article__image { visibility: hidden; display: none; } Roughly 2 in 5 American adults give themselves a grade of C, D or F on their knowledge of personal finance, according to a financial literacy survey by the National Foundation for Credit Counseling and NerdWallet. When it comes to debt, not understanding what you’re getting yourself into can not only cost you in dollars, but also make you miss out on what you really want to do with your money. NerdWallet spoke with four people who have shared the lessons they learned from their debt, including how they realized the errors of their ways and changed their money habits to work toward becoming debt-free. Consider the consequences Holly Johnson, a 35-year-old business owner from central Indiana, and her husband, Greg, racked up debt several times before realizing their mistakes.