There's a problem with branching paths and moral decisions in videogames: even if they are meaningful (few are), players can usually bypass the system by using multiple save files or other means to go in for another attempt and a different outcome.
While the same is still true for the online flash title One Chance, more work has been put in place to prevent you from "cheating." It's one of those games that doesn't try to be fun, but that's not to say the experience isn't entertaining. In six days, all life on Earth will cease to exist. It's up to you how to spend that time.
I recommend giving it a play. You'd be surprised how tense a game with this aesthetic can be. I'd also like to hear which conclusion you reached, since I'm not entirely sure how many possible outcomes there are.