Beginning vs end series quality:

JoJo: starts out on rocky but promising footing and eventually "grows the beard" into a cultural icon

Naruto Shippuden: Where the fuck did the Horse go?

AoT: Gainax ending

HxH: we're probably not getting an ending

One Piece: Oh, he's still going

Neverland: Series kinda went downhill after a promising start

At least that's my best attempt at translating

Going from the left to right represents how these anime stories started versus how they ended/are currently going:
With Jojo, the first part of the story is fairly different and somewhat basic compared to later parts, so it's shown as much less detailed than the rest of it.
Naruto Shippuden alternates between filler and plot several times throughout.
Attack on Titan gradually morphed into something way different from the story it started out as.
Hunter X Hunter is always on hiatus since the creator is suffering health issues and has trouble updating the manga.
One Piece just keeps going and going, pretty self-explanitory.
The Promised Neverland started out amazing and then got really bad really fast.