Magic, at the beginning of the season, I thought and rationalized exactly the way you do, and I expressed the same in a comment. After reading some of the responses, I began realized the error in my thinking. The knee jerk reaction is to assume that because you won the NC last year, you should be the preseason # 1 until you lose a game. That's one way of looking at it, and that's the way I saw it.
That's NOT how the voters or those that create the rankings see it. They don't use that kind of logic or criteria in forming their opinions. They look at the teams strength and weaknesses "on paper" (because no games have been played yet), and create their rankings. Since you're no kid, I know you are aware of all that I'm saying here.
The general consensus over the summer was that UConn lost the "core" of it's team last year, and would not be the same dominant team that it was last year. UConn had no returning All Americans on this team. Most felt that Notre Dame had the best/strongest/most dominant team THIS year, at least at the beginning, until some games were played, and the appropriate ranking adjustments could be made.