From my experience, when it comes to players, there are two types of them, regarding how they consider a game finished. One of them just moves forward with the story and missions until he or she gets “The End”, the credits and that stuff. The other one isn’t satisfied with fancy letters running up the screen and exhilarating CG Animation – They want more –They want all!!!
There could even be a third class, which is a mix. I am of this hybrid class. There are games that really deserve to be squeezed to the max. (They are fun, cool extras get unlocked, or it becomes a vice!) I can mention a few: GTA San Andreas, Saints Row, Crackdown, Need for Speed, etc.
Which kind of player are you? If you like playing a lot of games like I do, sometimes you have no other choice than play until the end, try another game and so on. But if you have had the same 5 games for the last 3 years, you can become an expert one ach one! I remember playing the Aladdin game on SNES over and over again just beating my best time to finish it … Ahh…those days… I could have bought the worse game out there, and still play it every day.