Vestigiality

Vestigial structures are those that used to serve a purpose, but through the process of evolution, no longer do. For example, an ostrich and an emu have wings, but they are no longer used for flying; the wings are vestigial. So are the human wisdom teeth.

One might think of vestigiality in matters beyond anatomy: 

• As a startup grows, some processes or structures become vestigial.
• As children move out from the house, some rooms become vestigial.
• As you grow mentally, some of your learned habits and beliefs become vestigial.

I know I'm stretching the boundaries of the concept, but I think the idea of vestigiality is useful when applied liberally: "In your life or business, what's something that used to serve a purpose but no longer does?"

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