Why is my script only running when object has been selected beforehand?

I have one other script attached to these which might be affecting it. Useful?

 using UnityEngine;
 using System.Collections;
 #if UNITY_EDITOR
 using UnityEditor;
 #endif
 
 [ExecuteInEditMode]
 public class ParallaxObject : MonoBehaviour 
 {
     public Camera connectedCamera;
 
     public float xSpeed = 0;
     //public float ySpeed = 0;
 
     public float cameraSizeRatio = 1;
 
     public bool resetPosition;
     public bool updatePosition = false;
 
     public Vector3 centerPosition;
     public Vector3 cameraCenterPosition;
 
     void Start ()
     {
         if (connectedCamera == null)
             connectedCamera = Camera.main;
 
         if (centerPosition == Vector3.zero && cameraCenterPosition == Vector3.zero)
             GetNewParallaxPosition();    
     }
     
     void GetNewParallaxPosition()
     {
         centerPosition = transform.position;
         cameraCenterPosition = connectedCamera.transform.position;
     }
 
     void UpdatePosition()
     {
         Vector3 _newPos = Vector3.zero;
         Vector3 _camPos = connectedCamera.transform.position;
 
         float _divideByScale = Mathf.Log(connectedCamera.orthographicSize);
         _divideByScale = Mathf.Log10(connectedCamera.orthographicSize);
         _divideByScale = Mathf.Log(connectedCamera.orthographicSize, 2);
 
         _newPos.x = centerPosition.x + ((_camPos.x - cameraCenterPosition.x) * (xSpeed / _divideByScale ));
         _newPos.y = centerPosition.y;// + ((_camPos.y - cameraCenterPosition.y) * (ySpeed / _divideByScale));
         _newPos.z = centerPosition.z;
 
         transform.position = _newPos;
 
         updatePosition = false;
     }
 
 
     void LateUpdate ()
     {
 
         #if UNITY_EDITOR
 
         if (resetPosition)
         {
 
             if(Selection.activeGameObject != gameObject)
                 resetPosition = false;
             GetNewParallaxPosition();
         }
 
         if (Selection.activeTransform == transform)
             return;
 
         #endif
 
         if (Application.isPlaying || updatePosition)
             UpdatePosition();
     }
 }