When I was younger, I used to play every single game I owned to completion. Not necessarily 100% completion, mind you, hunting down every last collectible was never my thing, but I did get to the ending of all my games. Now, I currently have ten games that I've started playing recently and I've only finished three of them. When I see the new batch of games coming out all the time, I can't help but wanting to play those instead of finishing the ones I already have. 
 
Is it because I've gotten older and no longer can dedicate the time needed to beating games like I used to when I was a kid? Or is it because there hasn't really been a slow season since last summer and the constant barrage of new games forces attention away from the ones I have currently in progress? Or maybe they just don't hold my attention the way they used to, which is probably a good thing, but also kind of sad.
 
I've decided to do something very simple, which will save me money and extend my enjoyment of the games I already have, and that is this: I won't buy another game until I beat them all. Well, maybe just the majority. Eight out of ten sounds good.

Trust me, that would be one tough decision to follow through. I say the same thing to myself week after week.

Dude I am in the same predicament, Hell I bought Rainbow Six Vegas (the first one) and never put the disk in! I never finished Too Human (I like it so its not the games fault) never finished Viking even though I have gotten to the last island twice I always have something else thrown in my face right when I about to be done. 
 
So Viking, Rainbow Six, Too Human, GTA4 (sad because its awesome) Batman AA (WTF AM I DOING?)  Shadow Complex, Dragon Age. Oh man...Ok I think I need to quit my job so I can get some real work done.

My theory? Disposable income.
 
When we were kids, most of us either had to save up allowance money to buy that one game we really wanted or wait for xmas, birthdays, etc for games as gifts (if we got lucky). So we didn't have an influx of 5-10 games to play all at once, instead having them portioned out over a more manageable period of time.
 
When we got jobs and started being able to afford any new game that caught our attention, we started being faced with the dilemma of "Which game do I play first?" and often getting into the problem of buying games faster than finishing them (especially with work, school, familes, etc getting in the way).
 
This might not apply to you specifically, but it's certainly something I've seen in my own history and those of people I know. Good luck with completing all those games before getting any new ones, hopefully they're all enjoyable!

 
I would buy some more games,and play a different game every day.

duder, i have the same problem. i have a crap load of games that i never get to beat. i've been working on them and modern warfare 2 is a game that i have beat. there are a lot of games that i have. i just bought psyconauts for $2 off of steam and i haven't touched it.

I understand, I'm trying to change that on me.
 
Pick 1 game only, play it all the time you can so you can get into it, and try not to play any other game until you finish it.

I own about 4 games. That's all. I have a job sure, but I really hate buying games because I rarely end up finishing them. I work at blockbuster, so I rent them there and if I find something I REALLY like, then I buy it. Renting one at a time is enough for me to finish most games.

I have a habit of buying games of what everyone else is playing on my friends list on STEAM or Xbox Live, so I can play with them when I get that game invite. As a result I have a wonderful back log of games. *rolls eyes*