A few issues come to mind about why this is happening. Firstly, the foul situation. It's difficult to maintain any type of consistency when the lineup is constantly being shuffled in the final ten minutes due to foul difficulty. I don't keep track of these things, but it's been rare lately for UConn to get into the bonus before the opponent, and it seems like the opponent usually gets there several minutes before UConn. Secondly, there's the rebounding. UConn can play great defense for 30 seconds, but if the other team gets 2nd and 3rd chances, eventually they're going to score. Additionally, it's tiring to play defense, especially if you have to play it for 45 seconds during a possession. On the other side of the court, UConn doesn't challenge the defense for the full shot clock. How many times is UConn holding the ball 30 feet out with ten seconds on the shot clock? The pass-it-around-the-perimeter offense doesn't force the defense to expend much energy. It seems like UConn is wearing down sooner than the other team - which might play into the foul situation as well.
On a separate issue, not to pile on about basketball IQ (or lack thereof), why on earth would you throw a full-court Hail Mary pass (which went untouched) with a lead and 1.5 seconds on the clock?