Hello. No matter how many times that i swipe the model camera keep returning back to one position. Am i done something wrong with this script please help me.THank you

using UnityEngine;
using System.Collections;

public class rotate : MonoBehaviour {

public Transform lookAt;
public Transform camTransform;

First of all, that is not a Vector3 * Vector3 multiplication, but Quaternion * Vector3.
Second, Vector3 * Vector3 is not defined in Unity, and definitely not like this.

Quaternion * Vector3 (in Unity) means rotating the Vector by the rotation defined by the quaternion, and is perfectly valid (in ‘real’ maths it would be quaternion * vector * ~quaternion, where ~ denotes the conjugate, but that is how the * operator for Quaternion * Vector3 is defined in Unity).

To the original poster: The problem must lie elsewhere. This script works absolutely fine.