@Walter Hinteler,
We are basically still new at the voting by mail.
I'm not sure how citizens of Germany are when it comes to voting, here it often takes a back seat to most everything. Civic pride and sense of duty and being part of the electoral process, is often lacking in the U.S.A.
Then there's the general lack of knowledge on the part of voters who do cast their ballots. So, a double hit. Indifference and ignorance.