Why is the object not reduced by 2 times?

Question

C++ / C#

Why is the object not reduced in size by 2 times?

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class NewBehaviourScript : MonoBehaviour
{
    public GameObject obj;


    void Start()
    {

    }

    void OnMouseDown()
    {
        obj.transform.localScale = new Vector3(transform.localScale.x / 2f, 
            transform.localScale.y / 2f, transform.localScale.z / 2f);
    }
}

If you create another script for this object, then everything turns out.
And this script is attached to the light, but this cube is attached to obj

Answer 1

Well, don't attach it to the light or whatever :)
Most likely, OnMouseDown is not called