History & CultureMental model
Why we do things because we've always done them.
Path dependence means early decisions lock in later ones, even when better alternatives exist. The 1,435-millimetre track gauge comes from Stephenson's railways of the 1820s; today more than half of the world's track uses it. Switching would cost billions. It's not the best solution that wins, but the one with the most already built on it.
Useful: For odd standards, don't ask "why is it like this?" but "when was this fixed?".
Source: en.wikipedia.org