Why Volkswagen May Have Risked It All by Allegedly Cheating on Emissions

Volkswagen was lauded as a "sustainable" and "clean" company weeks earlier.

“Any time you have standards or rules, some people will choose to cheat,” David Whiston, an analyst at Morningstar, told ABC News. “Volkswagen had made increasing its sales in the U.S. a priority. Part of the way to meet that goal of more U.S. sales was to increase diesel’s appeal with Americans. It appears those efforts are now wasted at least for quite a while.”

If Volkswagen had the technology to successfully pass an emissions test, why then was that same technology not in use when the car was being driven?

Whiston’s guess is that had it been in place, the car would not have met the driver's performance expectations.

"Rather than delay diesel introduction as others, including Honda and Mazda, did, Volkswagen decided to go ahead, but it appears that it was unable to reach emissions targets as it had hoped," Nerad said. "Thus it resorted to the software-hardware combination that deceived the EPA."

Jeff Thinnes, a former vice president for Daimler-Benz, told ABC News that "often these types of major corporate transgressions start with the belief that [a company] may be able to circumvent the law. When time passes and they are not exposed, they get more confident until they reach the feeling of invincibility. It’s about that time when the Tsunami hits.”

Nerad explained that Volkswagen was facing more restrictive emissions standards for diesels than it had encountered before.

"At the same time restrictive emissions standards are typically challenging to drivability and fuel economy," Nerad said. "This put Volkswagen engineers in a bind, while it prompted other manufacturers to delay or cancel their plans to introduce diesel engines in the U.S.”

"As CEO I accept responsibility for the irregularities that have been found in diesel engines and have therefore requested the Supervisory Board to agree on terminating my function as CEO of the Volkswagen Group," Winterkorn said in a statement. "I am doing this in the interests of the company even though I am not aware of any wrong doing on my part."

Volkswagen told dealers this week to halt sales of both new vehicles and certified pre-owned cars equipped with the 4-cylinder 2.0 TDI engine. Audi, which is owned by Volkswagen, also implemented a stop-sale for its model with that same engine, the A3 2.0 TDI.

Volkswagen's troubles could also cause it to lose the "world's most sustainable automotive group" title.

Earlier this month Volkswagen was named the world's most sustainable automaker for the second time by RobecoSAM. The German automaker ranked No. 1 in terms of climate strategy, conduct, compliance and anti-corruption compared to 33 other car companies.