I really like a post I saw awhile back that refines the idea of technical debt as an unhedged call option. (Original link is dead, so here's the wayback machine link and the HN thread.)

https://web.archive.org/web/20161223143702/http://higherorde... https://news.ycombinator.com/item?id=8777237

From the post:

> Call options are a better model than debt for cruddy code (without tests) because they capture the unpredictability of what we do. If I slap in an a feature without cleaning up then I get the benefit immediately, I collect the premium. If I never see that code again, then I’m ahead and, in retrospect, it would have been foolish to have spent time cleaning it up.

> On the other hand, if a radical new feature comes in that I have to do, all those quick fixes suddenly become very expensive to work with. Examples I’ve seen are a big new client that requires a port to a different platform, or a new regulatory requirement that needs a new report. I get equivalent problems if there’s a failure I have to interpret and fix just before a deadline, or the team members turn over completely and no-one remembers the tacit knowledge that helps the code make sense. The market has moved away from where I thought it was going to be and my option has been called.