I do remember hearing about this phenomenon before. It was many years ago when I was teaching an MBA course in IT Management and I can remember some of the (mature) students discussing negative value in the context of the Trabant, the famous East German mass-market car which was so rubbish that building them destroyed the value of the basic raw materials, let alone anything else. I did a quick google to see if I could find a reference to this and found that negative added value is well-known: in fact, during the 1990s, ALL of the world’s leading automobile manufacturers (with the exception of DaimlerChrysler) earned a negative added value!
You really do learning something new every day.
These opinions are my own (I think) and presented solely in my capacity as an interested member of the general public [posted with ecto]