Technical debt is financial debt's evil twin. You borrow time today (by writing quick, dirty code) to ship faster. But you have to pay interest on that debt every time you touch that code in the future.
Good Debt vs. Bad Debt
Good Debt: Conscious shortcuts taken to validate an MVP hypothesis. "We'll hardcode this pricing page because we might change pricing next week."
Bad Debt: Sloppy code written due to incompetence or lack of standards. "I didn't write tests because I was in a hurry."
How to Pay It Down
Allocating 20% of every sprint to refactoring is the standard rule. We believe in the "Boy Scout Rule": Leave the campground (code) cleaner than you found it. Every feature ticket should include a small refactor of the touched area.
At The Think, we audit codebases to identify these "interest payments" that are slowing down your feature velocity.