A quick note to link to my Gamepedia entry again.
I have actually owned Assassin's Creed on three occasions and I don't even like the game. Allow me to explain...
I bought it first, cheaply, on eBay for the Xbox 360 and played it briefly. I was so bored inside the opening hour that I never played it again. I managed to trade it in for the same price I paid for it. Skip forward 18 months and I became a huge AC fan after playing, loving and unlocking the Platinum Trophy in ACII on the PS3.
So after ACII came Brotherhood, which I also loved. So I decided that to complete the set I would need to own the first AC game. So I got it cheaply enough but could only find the Platinum version unfortunately. So that is the second time I have owned the game. And the third? It came as a bonus downloadable game with AC: Revelations last year.
Still haven't put more than an hour into the original though.