Actually they don't. mail-in-ballots take much loner to count and we have record turnout and mail-in-ballots. So this election will take much longer to count. And in some states they are still collecting votes.
And more votes are coming in in some states. It is like you do not know the election laws even as you talk about them. https://www.baynews9.com/fl/tampa/politics/2020/11/03/the-states-accepting-ballots-after-election-day-