That would depend on the who's leaving the message, if it even is one. It's not an efficient or east way to kill, and most people who fight with a blade would know that. It's undeniably dramatic though. If she was already in the process of dying from the other injury, it wouldn't have been a necessary hit and just something for show. If they wanted her to die faster, then a cut to the throat would have been both faster, easier, and more efficient.