VB.net - Um quadrado, descubra as diferenças

Vou apresentar duas maneiras de desenhar um quadrado com uma rotina.
Descubra as diferenças

            Dim estribo As Polyline = New Polyline()
            estribo.SetDatabaseDefaults()
            estribo.AddVertexAt(0, New Point2d(0, 0), 0, 0, 0)
            estribo.AddVertexAt(1, New Point2d(0, 1), 0, 0, 0)
            estribo.AddVertexAt(2, New Point2d(1, 1), 0, 0, 0)
            estribo.AddVertexAt(3, New Point2d(1, 0), 0, 0, 0)
            estribo.AddVertexAt(4, New Point2d(0,0), 0, 0, 0)


outra:

            Dim novalinha As New Line(New Point3d(0, 0, 0), New Point3d(1,0, 0))

            Dim novalinha1 As New Line(New Point3d(1, 0, 0), New Point3d(1, 1, 0))

            Dim novalinha2 As New Line(New Point3d(1, 1, 0), New Point3d(0, 1, 0))

            Dim novalinha3 As New Line(New Point3d(0, 1, 0), New Point3d(0, 0, 0))