That's kind of what I figured. I often try games that I'm not sure about if the price is right (I picked up the first Crysis for $20), but if I can only kind of get into it or don't enjoy it at all, then the series is dead to me no matter how awesome some of the sequels end up being.
It's one of the reasons I still haven't bought another Assassin's Creed game, no matter how many recommendations the later entries in the series got. It has moved way, way, way down on my list because of the impressions of the first game.