A vast proportion of software at work today is horribly over-engineered for its task. And I’m not talking about the interfaces, about having too many controls or options for the users. These are, indeed, terrible sins but they are the visible ones. The worst of the overengineering goes on under the surface, in the code itself.

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The most insidious cause of overengineering is over-generalizing. We will over-generalize anything given half a chance. Writing code to work with a list of students? Well, we might want to work with teachers and the general public someday, better add a base People class and subclass Student from that. Or Person and then EducationPerson and then Student. Yes, that’s better, right?

Only, now we have three classes to maintain each with their own virtual methods and interfaces and probably split across three different files plus the one we were working in when a one-line dictionary would have been fine.