Lunac said:
There's a few reasons, I guess.
Piracy is pretty rampant, especially here on the Codex (or at least more people here admit to it), and even if you factory in bandwidth costs, many people still don't pay a cent to pirate a game. You install it, crack it, play it for twenty minutes and form an opinion. I find it hard to believe most people who say X game is absolute shit played it for extended periods of time. Even then, some games can still be fun "for the lulz" without really being particularly good. See Oblivion for a game where you can spend a lot of time doing a lot of stupid shit, and have some giggles with mods, but ultimately is still pretty awful.
The second one is that you may buy a game expecting it to be good. I know several people here did, in fact, recently purchase Dungeon Siege III and felt they were let down (some did not, of course). Even if you feel a game is bad, you might want to spend time playing it or even replaying it, especially if it's relatively short, in order to try to extract some sort of value from it. "I paid my $50 USD, and I'd better get something out of this, even if it's just +30 hours on my Xfire profile!"
Standards on the Codex are also pretty different from what you see on other sites. FEAR 3, for example, is a completely competent game. It looks alright, it's mechanically sound, it's devoid of major bugs, it even has some novel ideas. But on the Codex, and in the eyes of many other gamers, competence isn't enough - you need, at the very least, some sort of hook, gimmick, or degree of excellence in one aspect before people here start to respect the game and start to consider it worthy of praise. Does it make the game "shit"? Not really, but it does mean it's completely unworthy of spending time on, unless you're the type that gets a kick out of ripping things apart and wants to do so from a position of authority (i.e. has actually played the game).
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