Psylocide
[09] Warrior
Thats because Assassin's Creed had an EXCELLENT ending. It tied up the story for the game, as well as sets up the sequel. If you think about it, its one of the best constructed endings in a video game ever. The way they did the game, so that you played Altair 99% of the time, gives you little reason to ask for more when Desmond's plot is left as a cliffhanger. Since they tied up Altair's plot, you get the ending you are looking for, while still leaving room for growth with Desmond, and piquing interest with the clues.
Well put, I found myself disagreeing with that post as well.