How can i destroy a gameobject?

When I destroy a gameobject instead of it disappearing it just returns to origin (and disappears from the hierarchy window)

test gameobject i made is destroyed no problems

code is:
void OnTriggerEnter (Collider col)
{
if (col.gameObject.tag == “Bullet”)

	{
		Destroy(gameObject);
	}
}

it works but I don’t know why it’s returning the gameobject to origin - any thoughts?

NB: Here is a video on youtube:

The blue cube is the test gameobject and has all the same properties as the zombie head as well as the same code

The code you provided here should work, but that alone is not enough information to go on to be able to tell if this is a bug or a user error. Please submit a bug report with a reproduction project attached. You can find information about bug reporting here: Unity QA - Bug Reporting - Unity

If you want to disable head visually use col.gameObject.GetComponent<MeshRenderer>(),
to be sure you reference desired GameObject use col.gameObject.GetComponent<GameObject>()