I strive to, especially with the 360's achievements.
Right now, I have 3 games with 1000/1000.
If these games didn't have achievements, I probably wouldn't have played them so much! :)
But hey! atleast my gamerscore goes up!
http://www.youtube.com/watch?v=iyLhpUPNPIs
360 IS OPERATIONAL AFTER 37 DAYS!