Second System Effect

Definitions

1. The tendency for the second version of a system to be over-engineered and bloated because designers include all the features they wished they'd had in the first version plus everything they learned. Coined by Fred Brooks in 'The Mythical Man-Month' (1975). The rewrite often takes longer, costs more, and introduces new bugs while trying to fix old ones.

   In plain English: The tendency to over-engineer a rewrite by adding every feature you wished the original had, making it take forever.

   Example: "The rewrite started as 'fix the pain points' and became 'reimagine everything' — classic second system effect. Three years later, it's still not shipped."

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