Man, why am I hoarding money on an abandoned space station? Why do I have to be told three times in five minutes that I need to shoot the limbs off the monsters? Why does shooting the limbs off the monsters even make sense?
Dead Space is a game that works in the moment. There are evil alien babies that scamper around walls and fling spikes at you from black tentacles. They don't just look small and deformed, they are literally mutant babies. That's totally messed up! There's a type of monster that resurrects other monsters, and every time you see it you freak out and fire all your assault rifle bullets, ignoring all other enemies and maybe getting yourself killed in the process.
A tentacle grabs you and drags you along the floor while you clumsily aim your gun at its big, glowing weak spot. It takes a second before you even realize you're not in a cutscene. When you finally figure it out, you have to scramble, aim your gun as fast as you can, and pray that you don't get smushed to bits. You are freaked out. But a couple days later, you wonder if the game really needed to repeat that scene two more times. You wonder why the tentacle has a giant glowing yellow pustule on it.
Dead Space is like that. Cobbled together, a little too cocksure, and a little too willing to cherry-pick ideas from better games to spackle over its holes. It has a store because Resident Evil 4 had a store. It has a gravity gun because Half-Life 2 had a gravity gun. It has audio logs from survivors detailing the plot because System Shock 2 (or Bioshock, if you prefer) had audio logs from survivors detailing the plot. Remember how Resident Evil 4 had a shooting gallery that gave you prizes? Let's do something with zero g basketball that gives you prizes!
These things are not nearly as noticeable when you're actually playing the game. You loved those other games! Later, you'll think about it more critically. You'll wonder who built a hallway on that space station that could only be traversed by using telekinetic powers from a robot suit to drag over a high tech hospital bed that (conveniently) also functions as a gap-spanning platform. Mankind has been building bridges for thousands of years, and that seems like about the least efficient way to do it. Buying flamethrowers from vending machines is ridiculous too, but that doesn't bother me because flamethrowers are awesome, and so is buying guns in games. The fact that this space-faring culture hasn't figured out how to build a corridor without leaving a gigantic hole in the middle of it that can only be traversed by magical psychic powers is not awesome, it's more like retarded. Show me the estimate that said it would be cheaper to equip every crewman on board that vessel with a telekinetic gauntlet than it would've been to just put a couple planks over that hole.
That's the problem with Dead Space, nothing stands up to close scrutiny. An alien trapped in an escape pod is jettisoned from your infected ship, and the military vessel coming to aid you picks it up, unknowingly putting the crazed alien in the middle of a 24-hour soldier buffet. That's some classic horror-movie "don't open that door!" set-up. It's enough to make you buy it... for a minute. But hey: how did one of those things take out a whole bunch of people armed with real-live guns when I've been killing them for four hours with a high-tech blowtorch? For that matter, why did they even let it out of the escape pod? If it was me in that situation and the pod I just saved from deep space had a frothing, flailing, scythe-armed alien creature in side I might think it over. Y'know, maybe make a cup of coffee before I opened the hatch and let him loose across the ship.
Taken bit by bit, it's exciting. Does that make it worth playing? More than once you're tasked with killing zombie aliens in a decompressed area of the ship, where the only sounds are your character's choking breaths as his suit's oxygen runs out. Those moments are pretty intense. If they were intense then, why aren't they intense now? Why don't I look back on them with the same excitement I had in the heat of the moment?
It's weird, is all. It's got enough of a game in there to be considered good, but all those niggling flaws add up. All that "me too!"-ism seeping out of its pores, all the unbelievable architecture in a supposedly realistic world, the contrived twist at the end, the glowing yellow lumps that serve as "shoot me here!" weak spots for enemies from the common grunt to the end boss.
These flaws are small. By themselves they'd be the 1% bad in a 99% great game. But 1% bad becomes 2% bad becomes 3% bad, and they keep adding up until you forget the zero-g sections and the scary resurrecting bat monsters and the tentacle babies. You forget the feeling of helplessness the first time you were overwhelmed by a swarm of bite-sized enemies (the kind that would be pistol-fodder in any other game) because the last hour of Dead Space is, under all the spike-flinging babies, an incredibly boring box puzzle with one box and a single track to push it along.
The best you can give Dead Space is a "good try." It makes me sad to say it, because every time I think of something bad, something they half-assed or cribbed from a game that did it better, it makes me think of something extremely scary, or fun, or at least a little engaging. It's just never enough.