The MPrin of technical debt incurred as a consequence of a platform component upgrade depends on how we incur the debt. If we incur the debt by installing the upgrade, and then performing only some of the work needed as a consequence of the upgrade, then the MPrin is the total cost of performing the work we deferred. If we incur the debt by deferring the upgrade, then the conventional definition of the MPrin is the cost of the upgrade plus the cost of any work necessitated by the upgrade, but not performed.
An aisle in the stacks of a library. Some libraries are upgrading their book tagging systems from barcodes to RFID tags — what is essentially a platform upgrade. When they do convert, every item in their collections becomes an instance of technical debt until it’s tagged with an RFID. A tagging technician can process about 1,000 items per day [Boss 2011]. It’s a big job.
In this latter instance, MPrin can increase over time if some of the work performed in the environment of the obsolete platform component, but subsequent to deferring the upgrade, must later be repeated after the upgrade is ultimately installed. This situation can be even worse if the work performed in the environment of the obsolete platform component fails after the upgrade, but the maintainers do not recognize the reason for the failure. In that case, an investigative effort is required first, to determine the cause of the failure. These additional costs are actually part of the debt retirement effort for the debt incurred by deferring the upgrade, but they’re usually accounted for — mistakenly — as routine operational expense.
References
[Boss 2011] Richard W. Boss, “RFID Technology for Libraries,” American Library Association, 2011.
Some libraries are upgrading their book tagging systems from barcodes to RFID tags—what is essentially a platform upgrade. When they do convert, every item in their collections becomes an instance of technical debt until it’s tagged with an RFID. A tagging technician can process about 1,000 items per day. It’s a big job. Available: here; Retrieved: November 21, 2017
In some instances, technical debt is actually a missing or incompletely implemented capability. If we retire the debt by completing the implementation, the MPrin is the cost of that effort, plus any training, testing, and lost revenue. If we retire the debt by halting or withdrawing the capability, the MPrin is the total cost of removal, plus testing and lost revenue.
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.
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.
