> 6: Anything less than 6 is too short even if it's really great. I loved Enslaved but it was too short for $60.
6-8: Short, but if it's all good than it's worth the purchase.
8-12: Medium length is fine. An eight hour story can be the perfect if the passing is right.
12-20: If the game has enough variety and the story is strong enough than the more the merrier. For example Tomb Raider never overstays it's welcome because it's so good that playing for 20 hours never gets old.
20+ Longer games can overstay their welcome. RPG can often go on for 100s of hours. Some fans love it. I prefer shorter adventures with more focus.








