Not sure if it fits this topic but I freaking loved Suikoden V, the problem is that it takes waaaay toooo long to start. Like... 5 hours or so. And players hardy give a chance to a game that drags that long right in the beginning. I literally had a saved game of around 5 hrs simply for when I wanted to start a new game to skip that horrible slow start.

MGS 5. I still haven't bothered to beat it. Enough is enough lol.

Persona 5 :O

Another one is Kingdoms of Amalur, I gave up on that one as the quest log just kept growing and growing and growing and growing to the point of oncoming panic attack. The combat was fun, story not bad at the start, world pretty nice to explore, yet way too many pointless side quests.

Horizon Zero Dawn. Gameplay gets repetetive real fast and it doesn't help that the story is quite boring because it's so predictable. I never finished that game because of that. I think I played about 20 or 30 hours and just stopped.

DragonQuest VII on 3DS. I don't mind a long JRPG, but this one just had way too much filler. The game just hands you busywork, along with long pointless cutscenes that don't even look cool. You know that cutscene that plays in Ocarina of Time when you open a chest? Imagine something like that playing everytime you open a door, change classes, get in your airship, etc.

The game has a nasty way of making you take the longest possible time to do anything. There's one dungeon where you are forced to walk through it five times. FIVE TIMES! just to get back to the village elder and talk to him.

I'm not kidding here. DQVII could have been a 60 hour JRPG if they cut the pointless fat out of the game. It takes thirty minutes to even see the end credits after you beat the final boss, because you still have to go around talking to all the characters you met over the journey.

Secret of Mana
Tried three times, always got bored after some hours in almost the same point

Tales of the Abyss. Dis tew much, the last 15 hours or so were incredibly frustrating. You travel from location to location just to watch a 1 minute cutscene or read some dialogue, and then its back to traveling back and forth. Plot wise, the mean guys wouldn't budge and die already... After you beat them all multiple times previously. Great game for 40 hours, terrible design all the way to the 60 hour mark/finale.

Xenogears also dragged on for a little too long. I know they were very ambitious and wanted to tell a full story, but I ended up logging in 63 hours even with the terrible second disc. The fact that the combat is slow, the character moves slow, the text speed is slow... And you get 20 hours in which you get to actually play 8 of.

Some of the old Dungeon in the early days of wow.. so many trash mobs and bosses to clear out it took hours.. literally hours.
And those old AV sessions which 1 match could take 6 hours.. old school wow players will know what i am talking about.

The Witcher 3 and Ni No Kuni