Question What are the conditions where Animator.Initialize() is called?

This method is heavy and we don't have control on when is it called. We already made a special pool where objects with Animator are not deactivated. We just move them to a far away location. This is so that Animator.Initialize() will not be invoked on reactivation. But even with this, Animator.Initialize() is still being invoked when an instance is requested and put to its correct position. I tried removing setting of parent but it still doesn't work. So I want to know what are the conditions when Animator.Initialize() is called. It can't be just setting the position because normal activated instances that are moved by gameplay don't call this method.