Wonder Egg Priority, super interesting premise, lovely character design, the story started out incredible but the ending is.... so, so enraging,especially for the fact that we had to wait for the last episode and they threw literally a bunch of stuff on the prior episodes to end up being supper squashed together and then... then nothing, back to square one.
Then, Supernatural, of course, I love hating on it's ending because this series is so well made in the sense that you first start it by the premise, by the lore and current plots but later on you invest your attention in the characters, they all are super interesting and lovable even if the longer the seasons go they end up being parody of themselves or, if your fav is not one of the brothers (the protagonists) you can say goodbye to any piece of personality and just turn them into maidens in distress or just plain being there doing nothing and even depowered.
The thing that I've noticed that I hate about the ending of these two shows is that you get invested in these characters, you see them dealing with a lot of crap, fighting constantly and their resolution ends up being dumb, pathetic, some in total solitude and rejecting all of the motivations that originally driven them or they end up dying with a death so out of character, with no dignity at all, illogical and very frustrating.
It's not like Devilman that while the ending is not a happy one you still get a stable closure, if you make a story going around Tragedy, I believe, and this is my personal take, that you either have to go full rock bottom like, total loss for the protagonist, a sad moving ending, or a happy one where effort is recompensated, where all that pain can actually bring peace of mind. You can also have something in between that depending on your mood it may lean to one side or another, but something that is.... muted down, so... unemotive, where even the characters feel out of canon, like robots or just... plain ignoring the events that happened around them like 2 minutes ago, idk I hate it 