Which of the following best explains why Clarence Saunders Keedoozle concept failed?

The Great Depression

It was inefficient.

Customers were used to full service.

Change does not work well in many business settings.

It failed because either the change did not work well in many business settings, or it was inefficient (due to the inefficiency of the conveyer-belt system). A more accurate reason is that the circuits couldn't handle the traffic during peak hour. The customer's orders were regularly mixed up. The conveyer-belt system was not fast enough or efficient enough to handle it.