Well it makes sense.
Dragon Age: Origins was meant as the First game. People say that the disk "Dragon Age: Origins - Awakening" (or however the title actually put it) was meant to be the second game... it wasn't. It was a DLC. A 20 hours of gameplay DLC. The game focuses on the player who is simply known through the game as the "Grey Warden". One of the last remaining ones though that spoils the story a bit. Point is... you travel to gather for a war, to defeat the ultimate goal, the ArchDemon.
Dragon Age blah blah blah Awakening was about the same Grey Warden (or a new High level Grey Warden from Orlais) who was dealing with the after affects of the Blight. In truth, Dragon Age II does not REQUIRE you to play Origins, but it DOES require you to know a bit about Dragon Age in general. Rather having read it, played it, blah blah blah.
The key reason is because of the Blight. At the beginning of Dragon Age II, your character and their family are escaping from "The Blight" which is like a Great War. The Darkspawn (vicious creatures from underground) rise into Fereldan and begin to kill things. Yay. Dragon Age II starts in the same time that the events of Origins are happening.
You can't say that it's not a good game just because it helps to have bought the first game ^_^ Why would you buy a game with a number like II or III if you didn't even play the ones before it? The key to it all is storyline and if you don't care enough about storyline to buy the first game, why care about it in the other ones enough to give it a bad rating? ^_^ The graphics confuse me at a few times though because it looks like it went from Full Screen to Wide Screen during some "Cutscenes".