The code is executing correctly,but output not coming

protected void Button1_Click(object sender, EventArgs e)
   {
       try
       {
           Thread tid1 = new Thread(new ThreadStart(this.Thread1));
           Thread tid2 = new Thread(new ThreadStart(this.Thread2));

           tid1.Start();
           tid2.Start();
       }
       catch
       {
       }
   }
   public void Thread1()
   {
       try
       {
           for (int i = 0; i < 100; i++)
           {
               ListBox1.Items.Add(i.ToString());
               Thread.Sleep(10);
           }
       }
       catch (Exception ex)
       {
           Label1.Text = ex.Message;
       }
   }
   private void Thread2()
       {
           try
           {
               for (int i = 0; i < 100; i++)
               {
                   ListBox2.Items.Add(i.ToString());
                   Thread.Sleep(50);

               }
           }
           catch
           {
           }
       }