From the information gathered previously, this Four-winged Thunder Tiger is not as wildly agitated as it appears on the surface. All of it is just a facade it puts on.
The reason for this behavior is simply to avoid showing any signs of being tamed, so that it can guard key sect areas without being suspected.
During the taming process, it occasionally displays an untamed demon-like temperament, sometimes even adopting an attacking posture.
However, it carefully controls the extent of its actions. During Lu Xuan's training sessions, it behaves as usual, only showing its aggressive side after the session is over.
If it were to attack Lu Xuan during the taming process, the only thing waiting for it would be severe punishment or even immediate execution.
Such troublesome behaviour after training not only allows it to maintain its untamed appearance but also prevents it from being punished, enabling it to stay in the taming stage indefinitely.