[dougpa]

It does have to be paid off. A business's technical division can, and inevitably will, become insolvent due to the accumulation of that debt. I take it you've never worked at a company which, after a fast & high-complexity period of startup-development, has had its development grind to a near-halt? Where it takes weeks to make a one line change? This is the analogous equivalent of insolvency for tech debt.

[gilbetron]

I disagree, it doesn't have to be "paid off", no one is waiting for the "money". Rather, design and code decisions may need to be addressed in the future to alleviate development friction.

I have worked in places as you describe, and tech debt is still a bad analogy. It isn't debt, but rather friction, which is a much better analogy.