I've been a Poll Clerk and Deputy Returning Officer in Canada in three elections. It takes a half hour to count the votes, and an hour to fill out all the paper work balancing ballots issued against ballots cast, spoiled ballots, and other stuff. Worse if the Poll Clerk's list of names crossed off doesn't match the number of ballots issued. That's usually a person's eye gliding over one name.
But results are in in three hours of polling, though it isn't official until a week later, the count my the DRO and Poll Clerk is only considered "preliminary" in Canadian law. Everything has to be counted again by the riding Returning Officer, or if the candidates are separated by less that 100 votes, a judge.