It's too long for me to post. Pretty much says only 20% of gamers ever finish a game, that includes GOTY titles.
http://www.cnn.com/2011/TECH/gaming.gadgets/08/17/finishing.videogames.snow/index.html?hpt=te_bn1
http://www.cnn.com/2011/TECH/gaming.gadgets/08/17/finishing.videogames.snow/index.html?hpt=te_bn1