Martin Fowler explains Technical. Debt.
"Doing things the quick and dirty way sets us up with a technical debt, which is similar to a financial debt. Like a financial debt, the technical debt incurs interest payments, which come in the form of the extra effort that we have to do in future development."
Technical debt is a self-evident phenomenon that is often ignored in school and universally ignored in the trade press. This often leads to unrealistic pressures, unreasonable customers, and to bad decisions. Everything has costs; you can't add features (or quality, or polish) without creating an offsetting liability.