Norvig's Law states "Any technology that surpasses 50% penetration will never double again"

Oftentimes, in rapid growth items like software adoption or stock prices, people excitedly report "it grew by 50%!"

If (for example) the adoption of the React JavaScript library in the workplace has reached 50% - it will never double again.

It's a simple mathmetical statement - it can't double past 50% again.

This law does depends what you measure, as sometimes, something can double multiple times past 50% growth (like a stock price).

But for something like software adoption, Norvig's law is absolute!