All that work and investment have been rendered void with the EPA's revelation.
What would lead a division of one of the world’s leading car companies to consider such action? Perhaps it felt under increasing pressure to live up to the grand growth proclamations made by its chiefs in 2007.
Perhaps it’s also an indication of how difficult it is for car makers to adhere to ever-more stringent emissions regulations with standard, non-hybrid powertrains.
Winterkorn’s statement in response to the EPA’s claims is contrite, and with good reason, for this scandal also risks affecting Volkswagen's global reputation, robbing it of consumer trust. As I write this, the firm's share price on the Frankfurt stock exchange has plunged.
Recovery will be a painful process that its rivals – including Toyota with its involvement in Takata’s defective airbag recall and General Motors with its faulty ignition switch scandal – know all too well.
The EPA is talking about hefty fines on Volkswagen. However, while any financial penalties will be hard to swallow, as will the attendant losses in terms of car recalls and sales, it is the loss of confidence from consumers that will hit it hardest, and for longest.
Read more on the Volkswagen emissions scandal:
How the Volkswagen story unfolded
How VW's 'defeat device' works
VW board anticipates more top-line casualties
European cars are affected, says German minister
PSA Peugeot Citroën leads calls for tougher emissions test procedures
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