Why when creating lines using LineRenderer it's creating too much objects?

Since I'm drawing a box it should have 12 lines but when running the game there are 24 objects. 12 are the lines but the other 12 seems to be doing nothing.

using UnityEngine;
using System.Collections;
using System.Collections.Generic;
using UnityEngine.Tilemaps;
using UnityEngine.WSA;

public class ShowMeshBounds : MonoBehaviour
{
    public Color color = Color.green;

    private Vector3 v3FrontTopLeft;
    private Vector3 v3FrontTopRight;
    private Vector3 v3FrontBottomLeft;
    private Vector3 v3FrontBottomRight;
    private Vector3 v3BackTopLeft;
    private Vector3 v3BackTopRight;
    private Vector3 v3BackBottomLeft;
    private Vector3 v3BackBottomRight;

    private void Start()
    {
        CalcPositons();
        DrawBox();
    }

    void CalcPositons()
    {
        Bounds bounds = GetComponent<MeshFilter>().sharedMesh.bounds;

        Vector3 v3Center = bounds.center;
        Vector3 v3Extents = bounds.extents;

        v3FrontTopLeft = new Vector3(v3Center.x - v3Extents.x, v3Center.y + v3Extents.y, v3Center.z - v3Extents.z);  // Front top left corner
        v3FrontTopRight = new Vector3(v3Center.x + v3Extents.x, v3Center.y + v3Extents.y, v3Center.z - v3Extents.z);  // Front top right corner
        v3FrontBottomLeft = new Vector3(v3Center.x - v3Extents.x, v3Center.y - v3Extents.y, v3Center.z - v3Extents.z);  // Front bottom left corner
        v3FrontBottomRight = new Vector3(v3Center.x + v3Extents.x, v3Center.y - v3Extents.y, v3Center.z - v3Extents.z);  // Front bottom right corner
        v3BackTopLeft = new Vector3(v3Center.x - v3Extents.x, v3Center.y + v3Extents.y, v3Center.z + v3Extents.z);  // Back top left corner
        v3BackTopRight = new Vector3(v3Center.x + v3Extents.x, v3Center.y + v3Extents.y, v3Center.z + v3Extents.z);  // Back top right corner
        v3BackBottomLeft = new Vector3(v3Center.x - v3Extents.x, v3Center.y - v3Extents.y, v3Center.z + v3Extents.z);  // Back bottom left corner
        v3BackBottomRight = new Vector3(v3Center.x + v3Extents.x, v3Center.y - v3Extents.y, v3Center.z + v3Extents.z);  // Back bottom right corner

        v3FrontTopLeft = transform.TransformPoint(v3FrontTopLeft);
        v3FrontTopRight = transform.TransformPoint(v3FrontTopRight);
        v3FrontBottomLeft = transform.TransformPoint(v3FrontBottomLeft);
        v3FrontBottomRight = transform.TransformPoint(v3FrontBottomRight);
        v3BackTopLeft = transform.TransformPoint(v3BackTopLeft);
        v3BackTopRight = transform.TransformPoint(v3BackTopRight);
        v3BackBottomLeft = transform.TransformPoint(v3BackBottomLeft);
        v3BackBottomRight = transform.TransformPoint(v3BackBottomRight);
    }

    void DrawBox()
    {
        SpawnLineGenerator(v3FrontTopLeft, v3FrontTopRight, color);
        SpawnLineGenerator(v3FrontTopRight, v3FrontBottomRight, color);
        SpawnLineGenerator(v3FrontBottomRight, v3FrontBottomLeft, color);
        SpawnLineGenerator(v3FrontBottomLeft, v3FrontTopLeft, color);

        SpawnLineGenerator(v3BackTopLeft, v3BackTopRight, color);
        SpawnLineGenerator(v3BackTopRight, v3BackBottomRight, color);
        SpawnLineGenerator(v3BackBottomRight, v3BackBottomLeft, color);
        SpawnLineGenerator(v3BackBottomLeft, v3BackTopLeft, color);

        SpawnLineGenerator(v3FrontTopLeft, v3BackTopLeft, color);
        SpawnLineGenerator(v3FrontTopRight, v3BackTopRight, color);
        SpawnLineGenerator(v3FrontBottomRight, v3BackBottomRight, color);
        SpawnLineGenerator(v3FrontBottomLeft, v3BackBottomLeft, color);
    }

    void SpawnLineGenerator(Vector3 start, Vector3 end, Color color)
    {
        GameObject myLine = new GameObject();
        myLine.tag = "FrameLine";
        myLine.name = "FrameLine";
        myLine.transform.position = start;
        myLine.AddComponent<LineRenderer>();
        LineRenderer lr = myLine.GetComponent<LineRenderer>();
        lr.material = new Material(Shader.Find("Particles/Alpha Blended Premultiply"));
        lr.startColor = color;
        lr.endColor = color;
        lr.startWidth = 0.03f;
        lr.endWidth = 0.03f;
        lr.SetPosition(0, start);
        lr.SetPosition(1, end);
    }
}

Inside the DrawBox there are 12 times I'm calling the SpawnLineGenerator that should create only 12 new gameobjects and 12 lines.

The script is attached to the Cube in the Hierarchy. When the game is running it's creating the green box with the 12 lines.

In the first screenshot I selected object number 12 line 12:

The next screenshot is showing the next gameobject number 13 and I did double click to show where it is position at:

Object number 13 to 24 are all at the same position like in the screenshot. But why it's creating them ? I want to create only the 12 green lines objects.