She's got defenses! ... It's just the folks that come after her keep gettin' stronger.
[He's not even going to touch the leak thing because HOW DARE YOU IMPLY ANYONE IN HIS KINGDOM IS DISLOYAL]
The first time, it was just one guy, and she managed to take care of him thanks to the guards. The second time, she got trapped inside the castle, and it took some outside help to get the troublemakers out.
... Last time, though... That was too close for comfort.