Each time i delete the game object, its mesh seem to be still existing. Is there something explicitly i have to do to delete the mesh?

I tried delete the mesh in OnDisable() using DestroyImmediate but the side effect is the mesh gets deleted if i hide the gameobject.

Am creating a mesh from scratch like this:

public class RouteCmp : MonoBehaviour {

    ...

    [SerializeField]
    Mesh m_Mesh=new Mesh();

    void Awake()
    {
        GetComponent<MeshFilter>().mesh = m_Mesh;
        GetComponent<MeshCollider>().sharedMesh = m_Mesh; 
    }

    public void BuildMesh()
    {
        ...
        ...

        this.Mesh.Clear();
        this.Mesh.vertices = vVertices;
        this.Mesh.colors = aColors;
        this.Mesh.uv = vVertUV;
        this.Mesh.triangles = nTriangleIndex;

    }
}

The image shows the before and after screen shots