FireMonkey TPathData flatten : M0,0

What is this extra M0,0

Just one is enough.

procedure TForm1.Button1Click(Sender: TObject);
var
  PathD : TPathData;
  po1 : TPolygon;
begin
  PathD := TPathData.Create;
  PathD.Data := 'M0,0 L0,100 L100,100 L100,0 L0,0 Z';
  Memo1.Lines.Add(PathD.Data);

  PathD.Flatten(); 
  Memo1.Lines.Add(PathD.Data);

  PathD.Flatten();
  Memo1.Lines.Add(PathD.Data);

  PathD.Flatten();
  Memo1.Lines.Add(PathD.Data);
end;

Extra M0,0 available here. Only one M0,0 should be. M0,0 = Move(0,0);

Out Memo1:

M0,0 L0,100 L100,100 L100,0 L0,0 Z 

M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 L0,100 L100,100 L100,0 L0,0 Z 

M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0
M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 L0,100 L100,100 L100,0 L0,0 Z 

M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0
M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0
M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0 M0,0
M0,0 M0,0 M0,0 M0,0 L0,100 L100,100 L100,0 L0,0 Z

How can I solve this?

(Yes this shape flatted. But same other circle, arc)