MPrin for missing or incompletely implemented capability
Last updated on December 13th, 2017 at 02:05 pm
In some instances, technical debt is actually a missing or incompletely implemented capability. For example, absence of a fully automated regression test suite can create difficulties for testing a complex system after a series of modifications. 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.
A concrete building under construction. Concrete takes about a month to fully cure, and until it cures it doesn’t reach full strength. If we waited for full curing before pouring the floor above, multistory concrete construction would be slow and very expensive. So we start on the next floor after only a few days. Because the floors of concrete buildings can’t support themselves for about a week or so, they need to be shored up by the floor below, and re-shored by the floors below that. The shoring constitutes a technical debt incurred because of the “incomplete implementation” (partial cure) of each floor. We retire that debt incrementally, floor by floor, by removing the re-shoring as the building gets taller. More about shoring and re-shoringBut 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, the assets involved can change. Moreover, if retiring the debt a revenue stream interruption, and that revenue stream grows significantly, the MPrin, which includes the lost revenue, can also grow significantly.
Technical debt associated with incompletely implemented capability presents unique problems, because debt of this kind can be retired 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 altogether. If that happens, retiring the debt completely would require removal of all artifacts that comprise the completed parts of the incomplete implementation. But full retirement can also require that we survey all components that interact with the retiring elements to determine whether they contain accommodations that are no longer necessary. Finally, we can choose a middle path, in which we adopt some parts that have been completed, reject other parts, and add whatever is necessary to create a limited version of what was originally planned.
It’s worth mentioning an important attribute of non-physical assets—software, procedures, legislation, regulations, and so on—that makes the technical debt associated with incomplete implementation so difficult to manage. 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 until the concrete is cured well enough to support itself. They constitute a kind of technical debt that must be “retired” before the building can be completed. The teams constructing the building could never forget to remove the shoring because it gets in the way of installing 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 being tried but didn’t work out. Many non-physical assets are perfectly functional carrying that kind of technical debt. The problems associated with that debt become evident with time, as the asset becomes increasingly difficult to maintain, extend, or defend.
It is 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.
The Metaphorical Principal of a technical debt that’s incurred as a result of a change in standards or regulations, internal or external, is the cost of bringing all affected assets into full compliance. Properly accounted for, however, the MPrin should include ripple effects, which are the changes in other assets that are required to keep them compatible with the assets that are directly affected.
Platform component upgrades often trigger the need to make changes in whatever sits atop the platform, to maintain compatibility with the platform. Those changes obviously contribute to MPrin. But less obvious are the contributions that arise from deferring the upgrade.
The MPrin of an asset that is subjected to new development or enhancement has some special characteristics. For an existing asset, new development can lead to duplication of capability. For new assets, unanticipated opportunities can transform into technical debt components that were not viewed as technical debt, without ever changing them in any way.
Some examples might help to clarify the differences between the principal of financial debts and the Metaphorical Principal of a technical debt. The examples to come in the next four posts are designed to illustrate the unique properties of MPrins of technical debts.
Expect the unexpected with technical debt retirement efforts, because they can conflict with ongoing operations, maintenance of existing capabilities, development of new capabilities, cyberdefense, or other technical debt retirement efforts. Policymakers can make important contributions to the enterprise mission if they can devise guidelines and frameworks for resolving these conflicts as closely as possible to the technical level.
The principal amount of a financial debt and the metaphorical principal of a technical debt have very different properties. They are so different that it’s wise to avoid using the term “principal” to refer to the metaphorical principal of a technical debt. We use the term MPrin.
