Как правильно использовать конструктор?

public class Circle
{
 public Circle()
 {
 }

 public void Draw()
 {
  //draw code
 }
}

class Program
{
 static void Main(string[] args)
 {
  var circle = new Circle();
  circle.Draw();
 }
}

public class Circle
{
 public Circle()
 {
   this.Draw();
 }

 public void Draw()
 {
  //draw code
 }
}

class Program
{
 static void Main(string[] args)
 {
  var circle = new Circle();  
 }
}