The thing with final bosses is that... they're the final boss. They are by definition your last encounter during the ending of the game.
So the developers have to make a choice, to either have an interesting and challenging final boss that the player will likely repeat 2-3 times, ruining the momentum and buildup of the ending sequence, or just have a simple and standard boss that will be beaten on the first try so that the momentum is maintained.
Then you have those games that are not designed to have bosses at all, but somehow felt the need to have a final boss, so it's just some clunky mess. Like Mass Effect, Uncharted 2, Deus Ex 3, etc.
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_foolmo_
'so I can potentially win the guru without getting the final right?' - BlAcK TuRtLe