Long elections waste immense amounts of money. they harass potential voters into apathy. They play into the horse-race, scandal-fed view of politics that feeds deeply unserious media coverage. They NOT INCIDENTALLY make it difficult/impossible for campaigns to deal with last-minute surprises.
O that's funny! That reminds me of the dirty secret of Pacific Northwest rowing, which is that everyone thinks summer should be the best rowing season, but it's really the worst...
It's a consequence of heavy participatory democracy. Primaries and then the General. And individual states hold theirs at different times. And you get multiple levels of government all at once: House, Senate, President, potentially locals & state elections too.