Maybe I'm weird or maybe I'm just old but I tend to play games until their finished, the only time I don't finish a game is if I get really stuck. I can't complete the final room in Portal Prelude, even after watching online videos of what to do, I still can't do it. I also keep getting killed right before the end of Dead Space 2, I'll go back to it and tough it out at some point. I had the same problem with the first Bioshock but I did go back and finish it. Last game I completed was my umteenth run through of Doom 3, currently running through Black Mesa and loving every minute of it.