Ward Cunningham introduced the “debt metaphor” to describe what can happen when some part of software work is postponed in order to get other parts out the door faster. He used this metaphor to highlight the idea that such postponement, while often a good choice, could have higher costs than people suspect. He likened the ongoing cost of postponed work to financial interest, and the eventual need to complete the work to the repayment of principal, observing that the interest charges could eventually become high enough to reduce the capacity to do other important work. Continue reading