OnEnable is never called for my script

I have two script on same object for one OnEnable is called but for other. I have tried this on primitive Cube with same result. For OnOverReaction onEnable is not called.

 using UnityEngine;
 using VRStandardAssets.Utils;
 namespace VRStandardAssets.Examples
 {
     // This script shows a simple example of how
     // swipe controls can be handled.
     public class OnOverReaction : MonoBehaviour
     {
         [SerializeField] private VRInteractiveItem m_Item;                                 
         private void OnEnable()
         {
             m_Item.OnOver += HandleSwipe;
         }
         private void OnDisable()
         {
             m_Item.OnOver -= HandleSwipe;
         }
         private void HandleSwipe()
         {    
         }
     }
 }

For UITint onEnable is called

 using UnityEngine;
 using UnityEngine.UI;
 
 namespace VRStandardAssets.Utils
 {
     public class UITint : MonoBehaviour
     {
         [SerializeField] private Color m_Tint;                                  // The colour to tint the Images.
         [Range (0f, 1f)] [SerializeField] private float m_TintPercent = 0.5f;   // How much the colour should be used.
         [SerializeField] private Image[] m_ImagesToTint;                        // References to the images which will be tinted.
         [SerializeField] private VRInteractiveItem m_InteractiveItem;           // Reference to the VRInteractiveItem which must be looked at to tint the images.
 
         private void OnEnable ()
         {
             m_InteractiveItem.OnOver += HandleOver;
             m_InteractiveItem.OnOut += HandleOut;
         }
         private void OnDisable ()
         {
             m_InteractiveItem.OnOver -= HandleOver;
             m_InteractiveItem.OnOut -= HandleOut;
         }
         private void HandleOver ()
         {
             // When the user looks at the VRInteractiveItem go through all the images...
             for (int i = 0; i < m_ImagesToTint.Length; i++)
             {
                 // and ADD to their colour by an amount based on the tint percentage.  Note this will push the colour closer to white.
                 m_ImagesToTint[i].color += m_Tint * m_TintPercent;
             }
         }
         private void HandleOut ()
         {
             // When the user looks away from the VRInteractiveItem go through all the images...
             for (int i = 0; i < m_ImagesToTint.Length; i++)
             {
                 // ...and subtract the same amount.
                 m_ImagesToTint[i].color -= m_Tint * m_TintPercent;
             }
         }
     }
 }

What am I doing wrong here?