That's in of itself, sad. The lack of efficiency is mind-bottling [1]. There were states with large populations that had 90-100% of results in a matter of hours.

[1] https://www.youtube.com/watch?v=rSfebOXSBOE

I'm not an American, can you explain how are able to determine a winner if the votes are still being counted?

It's not the simple national popular vote that determines the winner, there's this thing called an electoral college where the states get a certain number of votes. You end up with "swing states" which decide the election, and some states are dyed blue or red. So once enough votes have been counted in the swing states to determine their color, it's effectively over.

https://en.wikipedia.org/wiki/United_States_Electoral_Colleg...

Fundamentally it doesn’t matter whether 51% or 99% of a state goes for candidate A, assuming it is winner-takes-all in that state (a few aren’t.)

yeah California has between 5 and 7 million that will take weeks to count

Deadline for mail in ballot delivery is Nov 12. Have to be postmarked on the 5th, but they have a week to get to where they're going.

why does the seat of silicon valley take so long to count votes?

Are any voting system manufacturers even there? I guess votingworks is nominally there, but it's barely used.