Plots can be divided into at least five distinct parts. First is exposition, wherein the characters, setting, and conflict are introduced (each conflict carries its own plot diagram). Second is rising action; attempts to resolve the conflict take place. Third comes the climax, at which point the conflict is resolved. Fourth is falling action, where the results of the climax are revealed. Finally, the conclusion, wherein the future of the characters is wholly resolved, comes about, and the plot is finished.
"And they lived happily ever after" is a great conclusion. It leaves no room for ambiguity: everybody lives a joyous life, unfettered by trouble until they die. Any questions? I didn't think so. However, what was the latest, original work you saw such an ending in?
Definite conclusions have long been absent from literature, instead preferring to leave ends untied and open for interpretation (see Final Fantasy VII). The last great work to have any susbstantial falling action and conclusion was Fyodor Dostoyevsky's Crime and Punishment, where the main climax ends on page 95 of Signet Classic's 528-page edition. However, another work has finally come to take its place: Final Fantasy VIII. Unfortunately, while Crime and Punishment contains an intriguing falling action and conclusion, where we see the results of the climax painted in frightening detail, the technique failed for Final Fantasy VIII, instead leaving the final actions pointedly unmotivated, and leaving the player without a reason to care.
The main conflict of Final Fantasy VIII has nothing to do with Ultimecia; rather, it is Squall's internal conflict, as he struggles to determine what he really finds valuable in the world. This is why the game is centered around Squall: if it were not, it is unlikely that this conflict could be fully developed, let alone stand as the most prominent of the party's troubles.
This conflict is resolved long before fighting Ultimecia becomes a concern. Its climax occurs when Squall boldly slices the cables and rescues Rinoa from the Sorceress Memorial. Finally, he knows what is important, he knows that he must act on it, and he is with the woman he loves. Squall's problems are resolved.
Wait, though, the game is not over yet. You still have to take care of that big floating monolith. Oh, and remember Ultimecia? Yeah, you probably ought to do something about her, too. It certainly would be nice of you, saving the world from her reign of terror and destruction.
Everything which occurs after the scene at the Sorceress Memorial is falling action: it shows the player what happens to the characters after that defining moment. In a book, this would have been fine material. However, this is a game, and it presents a problem: as the main conflict has now been resolved, the player lacks motivation to continue. Squall and Rinoa are finally together! Life is good! That sorceress can do whatever she wants; we do not care. She poses no direct threat to the couple.
Theoretically, Ultimecia can possess Rinoa, and come between them in that way. The fact that she could be the undoing of the world is also a slight problem: after all, Squall and Rinoa rely on the world for their existence (even though Rinoa has demonstrated a keen ability to survive without oxygen). However, Final Fantasy VIII does not play up these threats appropriately. Rather than being presented as threats which may very seriously come between Squall and Rinoa, they are simply problems which the party ought to deal with. This leaves the player without a reason to care about killing the sorceress; without a reason to play. Without a reason to play, it is very possible that the player will not play. Then the game fails to be able to deliver any messages it may have for players after that scene. Certainly, the falling action does contain scenes which are important: Fujin and Raijin come to mind. However, there is no reason that the player feels obliged to go through these, aside from the simple desire for completeness.
The best games establish a very deep emotional link with the player, in which she and the pixels on the screen share each other's experiences. Once that link is lost, the game becomes shallow and feels futile. This is the flaw of Final Fantasy VIII: while it has an engrossing internal conflict -- Squall's struggle to determine his own priorities -- it fails to provide any further motivation once that conflict is resolved.
