[avianlyric]

Isn’t that just because individual human activities aren’t very precise, and for the most part, the position of the sun in the sky is enough for an individual to broadly synchronise themselves with the rest of society.

Unless someone is actually aiming to do a time coordinated task with others, you really need to know the time, or even the day-of-week to do stuff, because most human things in world aren’t actually occurring in small time sensitive windows.