the dash hole principle

The cigarette lighter receptacle has an amusing name. In my automobile and many others that I've seen, the present form isn't actually usable for lighting cigarettes. Now it's a round hole in the dashboard with a cover that's labeled as a power outlet. Over time, cigarette lighter receptacles turned into dash holes. The users of an object emphasized the secondary applications of it until the object itself dropped its primary application. It changed meaning through inventive usage.

Software users can be expected to act the same. Software developers should accept that the users, acting like humans, will adapt by introducing their own concepts and assumptions to a "finished" project. As DDD advises, the key is their language. When they speak about the software, and therefore the underlying design or data model, their words throw attention onto their interpretation of the "problem domain". They might describe data groups/categories and store their evolving understanding with rigid entries, like attaching "special" semantics to product identifiers that start with "Q". They might take several hours to run a series of automated preexisting reports, stuff the conglomerated figures into a spreadsheet, and then generate a chart - additional work which could all be accomplished by a computer in a tenth of the time.

The point is, software in the hands (and brains) of users can easily become a dash hole: an original design that came to be viewed much differently in practice. Developers who don't meet the needs of users will be bypassed manually as time goes on. In some cases, this may be a good approach. Some changes in usage just don't justify substantial software modifications. However, to state the obvious, not everyone is a good software analyst. Ad hoc solutions, enforced not by the software but by scores of unwritten rules, are prone to causing data duplication due to no normalization, chaos due to employee turnover or mere human frailty, and tediousness due to not thinking thoroughly about the whole process.

Dash holes function as adequate power outlets. But imagine if irritating dash holes could've been replaced with something designed to serve that purpose.