Why is operator-> implemented by operator * in STL STL library?

I read the source code std::deque

, I found the following implementations for _deque_iterator::operator->

and_deque_iterator::operator*

reference operator* const() { return *cur; }
pointer operator-> const(){ return &(operator*()); }

      

        
        
        
      

    

So my question is, why not just return a pointer cur

? Like this:

pointer operator-> const(){ return cur; }