What is Comprehension debt?

In any technical organisation the technology grows over time and the people who wrote the original systems may no longer be with the company. Whenever a person leaves an organisation they take with them the knowledge (and also the intent behind) the products that they developed.

This leads to a Comprehension Debt - we define that as a % of your product that no one who is at the company currently understands. This is easy to measure as you can look at who committed code (for example) and if they are still at the organisation. For the code that was written (and not since modified) by someone who has left - does anyone on the current team understand the why behind it?

This problem is going to become much more prevalent with the rise of AI coding. In this case all the code the AI has written is by default created by an entity that is not at the organisation - leading to a large comprehension debt. This can be remedied by code reviews of AI code before it is accepted to ensure the team understands what has been created.

Summary

All organisations have parts of their products that were developed by staff who are no longer at the organisation, but AI will accelerate this to dangerous levels. Put good procedures in place now to prevent problems downstream.