I have a variable that does not re-set on the closing of my program, the variable is modified on the trigger enter, why does it not re-set?

This is my code for modifing the variable

 var Counter =4;
 
 function OnGUI() {
     GUI.Label (Rect (10, 10, 100, 20), Counter.ToString());
 }    
 function Numbers(){
         Counter=Counter-1;
             print(Counter);
         }

 This is the code used for the destroying of the preFab        
 function update(){
         if (Counter==0){
             Counter=4;
 var Destroyed;
 var otherScript: Display;
 
 function OnTriggerEnter (hit: Collider) {    
             otherScript.Numbers();
         Destroy(gameObject);
     }