It's the same with me.
To me, it would be Magical Girl Lyrical Nanoha ViVid, the 4th season of the Lyrical Nanoha franchise. I hate how the Lyrical Nanoha franchise really jumped the shark in that one by ditching the whole "magical-meets-mechanical girls/women" thing that the first three seasons did so well and replacing it with some generic shonen battle anime with some fanservice sprinkled in for the lolicons. Also, we barely see the characters fight in situations that aren't mock battles or training. The worst part is that they only adapted the first 10 or so chapters of the manga (Yes, this anime was adapted from a manga which was spun-off from a magical girl show which was spun-off from a series of eroge games [named Triangle Heart] in the first place. Let that sink in.)! I know most anime adaptations are meant to promote the manga and all but this is pretty unacceptable. From what I've heard of the ViVid manga, it's not that much better than the anime adaptation.
Hey, at least the two main characters (Vivio Takamachi and Einhard/Einhart Stratos) are cute, the animation's alright (I guess), there's some good moments here and there (like Vivio's relationship/interactions with her two proud "mamas" [Nanoha and Fate, the two main protagonists of the first 3 seasons], the "Red Team VS. Blue Team" mock battle in episodes 6-7 was fun, it spawned a surprisingly good spin-off in the name of ViVid Strike! (which what I think MGLN ViVid should've been), and it's still better than from what I've heard of MRLN Force (the 5th season manga which was apparently so bad that it got cancelled halfway through the story and the creators of Lyrical Nanoha have forgotten it ever existed ever since [except for the redesigns of the devices which they later reused some of them for Innocent/InnocentS and the Reflection & Detonation movies]) though.