I'm calling the end of Game of Thrones
Just like every other hyperpopular long-running prime time opera... There will be a big blustery lead-up to the final episode, people who don't watch GOT will be eager for its ending as well, and then it'll finally end and the following 3 months will be the avalanche of complaints from those upset at how disappointing they thought the finale was.
Then will come the swarm of positive Nellys saying that the show finished before the books and we'll always have the true ending.
Until this process repeats itself with the books.