It depends. If the game is advertised to have features X,Y and Z and you get the impression that they should manifest around 40 hours of playtime and you don't see them, it isn't unreasonable to give test 10 hours more to be sure that the features are missing and then demand refund. Usually you can see the missing features faster and can demand refund after couple hours of playtime.
A smart developer would mention that features X,Y and Z are missing from this release even though they were promised/alluded to during several interviews. Even smarter developer would also mention that they are going to add the missing features and give some kind of timetable. Smartest developer wouldn't either promise features that cannot be finished before launch or delay the launch until the game is actually ready for launch.