On 18 September 2015 it became public that Volkswagen had used illegal software in its engine control to cheat emissions tests. On 9 October a Börsen-Zeitung editorial wrote that at VW the fear of failing and being dressed down by a superior, vom Vorgesetzten abgekanzelt zu werden, had apparently been much stronger than the sense of wrongdoing. In December the chairman of the supervisory board, Hans Dieter Pötsch, said at a press conference in Wolfsburg that it had been “a chain of errors that were allowed to happen”. He added: “There was a mindset in some areas of the company that tolerated breaches of rules.” The chief executive, Matthias Müller, named the goal: to discuss more openly and to allow mistakes, Fehler zuzulassen.