Technical debt and design debt are synonymous  metaphors referring to the eventual consequences of sloppy software architecture and rushed software development. Code debt refers to technical debt within a codebase. Ward Cunningham first drew the comparison between technical complexity and debt in a 1992 experience report:

Shipping first time code is like going into debt. A little debt speeds development so long as it is paid back promptly with a rewrite... The danger occurs when the debt is not repaid. Every minute spent on not-quite-right code counts as interest on that debt. Entire engineering organizations can be brought to a stand-still under the debt load of an unconsolidated implementation, object-oriented or otherwise.

Ongoing development in the upstream project can increase the cost of "paying off the debt" in the future.  A team should take opportunities, on a regular basis, to pay back (or pay off) this debt.  Either reserve a percentage of your development cycle or dedicate an entire cycle to complete this work.  If you don't, it will come back to haunt you.  If your kludge of a solution doesn't come back to bite the development team, it will probably haunt the help desk, support team, or someone else downstream.

Just like regular debt, you're going to have to pay it back sooner or later.  As a former Manager of Software Engineering and now as an advisor to a customer, I've seen (and see) what technical debt can do to the velocity of a team.  It robs them of precious time, after the fact. The development team buys into the idea that doing things the wrong way, to save some time in the interim, is worth the risks and the overall cost.  This is a really short-sided thought process.  Technical debt is like getting a loan from loan shark who roles dice to decide what your interest rate is.  So, if you don't need to take the risk, don't do it.

Be honest with your customer, your team, and yourself.  Estimate your work and stand by your estimate.  Don't let someone else tell you how long it will take to deliver quality work.  If you have to, you'll just have to deliver less work.  That is, don't take on the debt in the first place.

[HT]: Wikipedia

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