Here's what most people that are not from the US don't understand:
When I go to vote on election day, I'm not voting for one person/party or even three people/parties. The typical ballot in my neck of the woods is double sided and has ~30 questions: National elections (President, HoR rep, maybe senator), state elections (Governor, SoS, local rep/senator, corporation commission, referendums/ballot initiatives), county elections (sheriff, judges), city elections (mayor, city council, dog catcher), and funding questions (bond overrides and the like). I'm probably forgetting an item or 10 on that list.
I never had 30 elections on one day in Germany (I think 5 was the absolute maximum) as we elect fewer positions in general and don't combine most elections on one day. Usually the federal election is the only vote on that day with some states specifically moving their state election day by one week to avoid a clash. The only usual combination is regional/European elections or state/regional elections for the small states. Referendums (there only a few) are usually tacked onto another election if there is one in a reasonable timeframe.
The elections each use a seperate ballot (and often seperate ballot box) and are counted one after the other with the most important election being counted first while the rest is still locked away in sight.
But yeah, for 30 ballots that system might break down.
When I go to vote on election day, I'm not voting for one person/party or even three people/parties. The typical ballot in my neck of the woods is double sided and has ~30 questions: National elections (President, HoR rep, maybe senator), state elections (Governor, SoS, local rep/senator, corporation commission, referendums/ballot initiatives), county elections (sheriff, judges), city elections (mayor, city council, dog catcher), and funding questions (bond overrides and the like). I'm probably forgetting an item or 10 on that list.