As someone who works ten hour days every day I have found that my time is limited to play games of any sort.  Especially when the game requires a steep learning curve.  The is one of the reasons why I have not started to play Civ 5.  I have it downloaded and installed via Steam but I have had zero time to play it and when I do have time I'm scared that I won't have enough time to get into it before it's time to go to be at night.  
 
See, I've never played a Civ game before.  I really want to give this one a try but I just don't think that I will have the time necessary to dedicate to it.  :(