Whereas interest paid on a loan is tax-deductible, debt increases the risk of stockholders which drives down the price of the stock. The interest rates on Federal Student loans are usually low and the student has a long period in which to pay back the borrowed money. An authorized user essentially piggybacks on the credit of a friend or relative, entitled to use the credit afforded to the cardholder, but without the legal ramifications to pay the bill, points out Bankrate. Simply put, the first one, if allowable debts exceed income, will see things like credit card debt wiped out completely.