After all, everyone in the world already knows that the dig site on Mars houses the gateway to Hell. Taking those rules into account, it's safe to say that the nameless marine in Doom 3: Resurrection of Evil must be the most depressed, suicidal individual in the history of human society. If they do, it's not death at the hands of Hell's freakish, ravenous minions. Usually, people don't go out purposefully seeking death.