Financial debt is a good analogy, but there is a crucial difference: technical debt is not fungible. Cleaning up one kind of issue in your code doesn't affect

Financial debt is a good analogy, but there is a crucial difference: technical debt is not fungible. Cleaning up one kind of issue in your code doesn't affect other kinds of issues, and you can end up with fundamental architectural problems that no amount of testing or clean up can compensate for. You can handle some issues incrementally (eg adding tests), but some issues are going to be so fundamental to your system that you can only handle them by making a lot of changes all at once. You can't refinance technical debt!