Every summer, I think about Haruhi: Endless 8s. In the 2000s, one of the most popular animes out there was The Melancholy of Haruhi Suzumiya, a slice of life anime about a girl who doesn't know she's god and was based on a novel series by the same name.
Now, there's an arc in the books called Endless 8s where the characters get stuck in a timeloop and it's not that many pages in the book. So, Kyoto Animation was going to make that arc like 2 episodes long and then move onto the next arc. Unfortunately, that next arc ended up becoming a movie instead so they had this 8 episode hole in the series which they needed to fulfill their contractual obligations.
So, what did they do? They reanimated the same episode 8 times. And broadcasted them one per week the entirety of summer 2009. They didn't just rerun the same episode.
They redrew every single frame with slightly different camera angles, or clothes, and had the voice actors redeliver their lines. Every episode even had a different director. The timeloop, 8 episodes long, over and over.
At first, people on anime boards thought it was just a joke. They couldn't possibly do this all summer for 8 weeks right? Wrong. They absolutely did and it caused incredible meltdowns online. People were furious online that Kyoto Animation would do this to them. It made the Great Naruto Filler arc (which deserves it's own post) look good by comparison.
We will never get anything that avant garde ever again in anime and frankly, I don't think anyone can handle it.