当方法退出时,为什么此接口没有正确释放?

program Project1;

{$APPTYPE CONSOLE}
{$R *.res}

uses
  Winapi.Windows,
  System.Generics.Collections,
  System.SysUtils;

type
  TForm1 = class
  public
    Events: TList<TProc>;
    constructor Create;
    destructor Destroy; override;
  end;

  TTracingInterfacedObject = class(TInterfacedObject)
  public
    function _AddRef: Integer; stdcall;
    function _Release: Integer; stdcall;
  end;

  ISharedPtr<T> = interface
    ['{CC9EE6C5-F07B-40E5-B05D-2DFDBD3404A1}']
    function Get: T;
    function GetRefCount: Integer;
  end;

  ICatalog = interface
    ['{F421BBA8-8DA3-47EE-ADB9-DED26747472E}']
    function GetView: ISharedPtr<TForm1>;
    property View: ISharedPtr<TForm1> read GetView;
  end;

  ITree = interface
    ['{A1E2F71B-124B-48DB-B038-5F90AC5BE94B}']
    function GetId: TGUID;
    property Id: TGUID read GetId;
  end;

  TSharedPtr<T: class> = class(TTracingInterfacedObject, ISharedPtr<T>)
  private
    FObject: T;
  public
    constructor Create(const AObject: T);
    destructor Destroy; override;
    function GetRefCount: Integer;
    function Get: T;
  end;

  TCatalog = class(TTracingInterfacedObject, ICatalog)
  private
    FView: ISharedPtr<TForm1>;
  public
    constructor Create;
    function GetView: ISharedPtr<TForm1>;
  end;

  TTree = class(TTracingInterfacedObject, ITree)
  private
    FView: ISharedPtr<TForm1>;
  public
    constructor Create(const AView: ISharedPtr<TForm1>);
    function GetId: TGUID;
  end;

function TTracingInterfacedObject._AddRef: Integer;
begin
  OutputDebugString(PChar(ClassName + '._AddRef'));
  Result := inherited _AddRef;
end;

function TTracingInterfacedObject._Release: Integer;
begin
  OutputDebugString(PChar(ClassName + '._Release'));
  Result := inherited _Release;
end;

constructor TForm1.Create;
begin
  inherited;
  Events := TList<TProc>.Create;
end;

destructor TForm1.Destroy;
begin
  Events.Free;
  inherited;
end;

constructor TSharedPtr<T>.Create(const AObject: T);
begin
  inherited Create;
  FObject := AObject;
end;

destructor TSharedPtr<T>.Destroy;
begin
  FObject.Free;
  inherited;
end;

function TSharedPtr<T>.Get: T;
begin
  Result := FObject;
end;

function TSharedPtr<T>.GetRefCount: Integer;
begin
  Result := FRefCount;
end;

constructor TCatalog.Create;
begin
  inherited Create;
  FView := TSharedPtr<TForm1>.Create(TForm1.Create) as ISharedPtr<TForm1>;
end;

function TCatalog.GetView: ISharedPtr<TForm1>;
begin
  Result := FView;
end;

constructor TTree.Create(const AView: ISharedPtr<TForm1>);
begin
  inherited Create;
  FView := AView;
end;

function TTree.GetId: TGUID;
begin
  Result := TGUID.Empty;
end;

procedure Main;
var
  Catalog: ICatalog;
  Tree: ITree;
  Func: TFunc<TGUID>;
  Events: TList<TProc>;
  Event: TProc;
begin
  Catalog := TCatalog.Create as ICatalog;

  Events := Catalog.View.Get.Events;

  Event := procedure
    begin
    end;

  Events.Add(Event);

  Tree := TTree.Create(Catalog.View) as ITree;

  Func := function: TGUID
    begin
      Result := Tree.Id;
    end;
end;

begin
  Main;

end.

我在决赛中设了一个断点 end.

Debug Output: TSharedPtr<Project1.TForm1>._AddRef Process Project1.exe (3456)
Debug Output: TCatalog._AddRef Process Project1.exe (3456)
Debug Output: TSharedPtr<Project1.TForm1>._AddRef Process Project1.exe (3456)
Debug Output: TSharedPtr<Project1.TForm1>._AddRef Process Project1.exe (3456)
Debug Output: TSharedPtr<Project1.TForm1>._AddRef Process Project1.exe (3456)
Debug Output: TTree._AddRef Process Project1.exe (3456)
Debug Output: TSharedPtr<Project1.TForm1>._Release Process Project1.exe (3456)
Debug Output: TSharedPtr<Project1.TForm1>._Release Process Project1.exe (3456)
Debug Output: TCatalog._Release Process Project1.exe (3456)
Debug Output: TSharedPtr<Project1.TForm1>._Release Process Project1.exe (3456)
Source Breakpoint at $0047F675: C:\Users\Admin\Documents\Embarcadero\Studio\Projects\ViewFail\Project1.dpr line 168. Process Project1.exe (3456)

• 这棵树被添加了一次,从未释放过,这不是我所期望的。

为什么会这样?是否有一个参考周期在我缺失的地方?