Debt is borrowed time. When you borrow money, you are spending income you have not yet earned, and the cost of that borrowing is interest — the price you pay for using someone else's money. Not all debt is equally dangerous. A business loan taken to generate revenue that exceeds the interest cost can be a smart tool. But consumer debt — credit cards, buy-now-pay-later schemes, personal loans taken for lifestyle spending — tends to work against you. Here is why: compound interest works in reverse when you are the borrower. The longer you carry a balance, the more you owe, and the more of your future income gets redirected to paying for the past. A ₦50,000 phone bought on credit at 30% monthly interest can cost ₦80,000 or more before it is paid off. The item depreciates. The debt grows. The lesson is not to avoid all debt — it is to understand exactly what debt costs before taking it, and to ensure the thing you are borrowing for is worth that cost.