Why is therianthropy involuntary? A definitional boundry.

I label my therianthropy as involuntary because it is not up to me when I want to growl or when I am behaving animalistic. I dont get to choose where or when I am like that. Yes, there are specific moments and situations that trigger the animal like responses but I cannot choose that in this very moment I will act or feel as a wolf. I mean shifts and etc.
I can consciously try to trigger it but that is not, what I think therianthropy is about. My wolf behaviour comes and goes independently on what I think or whether I want it or not.
Yes, I chose I will call myself therian and yes, I chose to label myself as a wolf because that is the closest thing which is fitting my experiences.