Because it was shit.
I feel like this game really encompasses all of the problems that modern vidya has
The first game was shit.
The third game was shittier.
I have no idea about 2.
That game is a LITERAL fanfic
It even had goddamned oc's
That game was so fucking boring, I don't get why Holla Forums likes it so much
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It's either the shittiest or somewhere in between. You can at least trudge through the first one just to see where it goes. The other ones either aren't engaging enough or fun enough to justify the hassle.
I'm inclined to agree with it a bit because of Lamb's sudden extreme importance and the massive faction within Rapture that even started their own religion based on her psychobabble that absolutely none of which even remotely mentioned as happening in the first game
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oh boy you're gonna love it
Textbook example of unnecessary sequel. I didn't want to play as big daddy besides the little bit in biococks 1, making the "cherry on top" into a full game fucks up the entire experience. Everything about it was unnecessary. Biococks 1 actually had moments where some playstyles were better than others. B2 was simply the most bland, linear, and forgettable game in terms of everything. You could tell the devs simply didn't give a fuck.
As for the games that encompasses all of the problems that vidya has, look at e-sports shit like Overwatch, and more narrative walking sims like Life is Strange. Life is Strange is a problem in the sense that people simply don't want a game anymore, they want something that makes them "feel" deep. They don't care how they get their fix, as long as "emotional narrative" is on the tin, they want to play along and will do anything to defend that narrative, no pun intended.
As for the problem with Overwatch, it's a textbook example of the "flavor of the month" stage of evolution that the industry is at. People want to pay games where they can do next to jack shit and be able to show off to their friends how excellent their shitty "play of the game" was, whereas classic vidya like Quake actually required some form of skill to pull off a lot of tricks that are needed to play above a retard level. Don't get me started on how it's gonna open up a floodgate of socially exceptable waifushit from here on out.
So? kotor 2 did the same thing with Kreia and changing Revan's reasons for falling, but no one gives Obsidian shit for that.