Last updated on June 15th, 2021 at 11:31 am
In some instances, the metaphorical principal (MPrin) of a technical debt is a missing or incompletely implemented capability. For example, absence of a fully automated regression test suite can create difficulties for testing a complex system. Defects can slip through. That would result in reduced productivity and velocity. In this case, the projected cost of implementing, testing, and documenting the test suite, and training its users, would constitute the initial MPrin of the outstanding technical debt. This definition differs from some definitions, because it includes testing, documenting, and initial training. In general, from the enterprise perspective, when identifying the MPrin associated with missing or incompletely implemented capabilities, we must include all artifacts necessary to eliminate reductions in productivity and velocity.
But even if we include these items in the conventional definition, MPrin at retirement can exceed the savings at the time we incurred the debt. For example, in the interval between origination and retirement the assets involved can change. Moreover, if retiring the debt causes a revenue stream interruption, the MPrin, which includes the lost revenue, can be significantly larger than the initial MPrin.
Unique problems of incompletely implemented capability
Technical debt associated with incompletely implemented capability presents unique problems. We can retire it in three distinct ways. First, we can complete the implementation. The MPrin associated with this approach can grow beyond the initial cost of completion, for the usual reasons. Second, we can cancel the capability. If we do, retiring the debt completely would require removal of all artifacts that we no longer need. Finally, we can choose a middle path. In the middle path we adopt some parts that have been completed. But we reject other parts, and we add whatever is necessary to create a limited version of what we originally planned.
Special challenges of non-physical assets
Invisibility is an important attribute of non-physical assets such as software, procedures, legislation, regulations, and so on. Technical debt associated with incomplete implementation is difficult to manage in such assets. For example, the image above shows several levels of a concrete building under construction. The vertical members between the levels are part of a shoring system that supports the levels of the building. Shoring is necessary until the concrete floors cure well enough to support themselves. Shoring constitutes a kind of technical debt that must be “retired” before the building is complete. The teams constructing the building could never forget to remove the shoring because it obstructs installation of the windows and walls.
But things are very different with non-physical assets. It’s easy to forget to remove intermediate artifacts, or elements that were part of attempts that didn’t work out. Many non-physical assets are perfectly functional carrying that kind of technical debt. That debt becomes evident with time, as the asset becomes increasingly difficult to maintain, extend, or defend.
It’s this property of non-physical assets that makes technical debt management so much more difficult than it is with physical assets. Not more important, just more difficult.