while blue US swing states take DAYS with machines?

Why can Argentina count 25–30 million paper ballots in hours, while blue US swing states take DAYS with machines?

from Revolver News: It’s quite astonishing that the United States of America, one of the most powerful nations in the world, struggles to hold streamlined elections. We’ve gone from having election results on the same night or in the early hours to prolonged counts of sketchy ballots behind closed doors, with the winner remaining unknown […]