Above: Guybrush Threepwood, mighty pirate.The only accurate blanket statement anybody can make is that there are no accurate blanket statements. But this one is close: voice acting never makes a game better, and can only make it worse.
Let's acknowledge the exceptions early. Plenty of games have had good or even great voice acting (The Darkness and Half-Life 2 come to mind). I'm saying that the presence of recorded dialogue is, at best, a net zero for the overall quality of a game, and more often, it's a negative. The history of atrocious voice acting is well documented elsewhere. Yet the campy grandeur of the original Resident Evil is, in its own way, one of the biggest reasons to enjoy that game. It's the games with passable voice acting that can be more insidious -- games where speech adds nothing, while slowing down gameplay or, more often, hammering you with the same few soundbites over and over.
Lots of games suffer from repetition. Recall Marcus Fenix growling "Nice!" after every successful active reload. Resident Evil 4 is still my favorite game of all time, but one of its two noticeable flaws was the merchant's boundless curiosity about what you were buyin' or sellin'.* Recently, Ghostbusters, a game with better-than-average voice acting, decided it would be a good idea for Egon to shout "Aim high!" every four or five seconds during battle. What's the logic behind stuff like this? I think it's, "We've paid for the actors' time; we'd better get our money's worth!"
Nowhere is this a bigger problem than in adventure games. Games like Tales of Monkey Island rely on dialogue for everything. The story is told largely through character interaction, and many puzzles can be solved only by sweet-talking the characters who have what you want. The voice acting is just fine in this game -- totally serviceable. It is not, however, so good that I want to hear the same handful of lines repeated dozens of times in the course of a five-hour game.
Guybrush has only a few stock responses when you attempt to use an item somewhere it has no use. He says something clever about almost each one. And he says the same clever line every time. It's possible -- no, likely -- that many of you are smarter than me, and in the course of playing an adventure game aren't reduced to trying to use every item in your inventory with every hotspot on the screen. That's just how I roll, and in the old days, when the written rejection was superimposed over the action, it was easier to ignore.
Worse, in this case, is that the game seems to provide the player with more dialogue choices than they actually recorded for Guybrush. You'll see four different jokes to choose from, but when you select one Guybrush doesn't say it. He says some canned, plot-advancing line, one that may or may not also be funny. Then, the player has no option to go back and explore the other lines. I think this is also a case of the producers trying to maximize their dollar: you pay the actors as little as possible, and use their work as much as you can. A sensible business decision; not great for the gameplay.
Tales of Monkey Island is pretty fun (my review is coming later this week). Still, I couldn't help but think that it would have been better if the developers had gone the text-only route. They could have packed more jokes and deeper dialogue trees into the game, while saving on costs and even bandwidth for digital distribution. Instead, they hired actors and ended up making, perhaps, a lesser game.
(Then again, it's totally possible that you can choose to disable the speech and enable subtitles. I didn't even think to check that until right this second.)
*The other flaw: QTE knife fight against Krauser.
