overriding new and delete operators...and didn't work as I expected

I have code like bellow...

class AncestorClass
{
public:
	AncestorClass()	{}

	virtual ~AncestorClass()	{}

	static void* operator new(size_t _size)
	{
		cout << "AncestorClass new" << endl;
		AncestorClass*	_ptr	= ::new AncestorClass();
		if (_ptr)	_ptr->Initialize();
		return _ptr;
	}
	static void operator delete(void* _ptr)
	{
		cout << "AncestorClass delete" << endl;
		if (_ptr)	((AncestorClass*)_ptr)->Finalize();
		::delete	_ptr;
	}

	virtual void	Initialize()
	{
		cout	<< "Ancestor Initialize" << endl;
	}

	virtual void	Finalize()
	{
		cout	<< "Ancestor Finalize" << endl;
	}
};

class DerivedClass : public AncestorClass
{
public:
	DerivedClass()	{}

	virtual ~DerivedClass()	{}

	static void* operator new(size_t _size)
	{
		cout << "DerivedClass new" << endl;
		DerivedClass*	_ptr	= ::new DerivedClass();
		if (_ptr)	_ptr->Initialize();
		return _ptr;
	}
	static void operator delete(void* _ptr)
	{
		cout << "DerivedClass delete" << endl;
		((DerivedClass*)_ptr)->Finalize();
		::delete _ptr;
	}

	virtual void	Initialize()
	{
		cout	<< "DerivedClass Initialize" << endl;
	}

	virtual void	Finalize()
	{
		cout	<< "DerivedClass Finalize" << endl;
	}
};

int main()
{
	AncestorClass*	t	= new DerivedClass;
	delete	t;

	return 0;
}

What I expected result is...

DerivedClass new
DerivedClass Initialize
DerivedClass delete
DerivedClass Finalize

but what in real is...

DerivedClass new
DerivedClass Initialize
DerivedClass delete
AncestorClass Finalize

Where's my problem and how to fix it?

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