Work and Wealth

At the beginning of the movie, the nuclear silo operators are given launch codes and tasked with launching a retaliatory attack. In this test scenario, they have no outside communication besides the code that was provided to them. In the end, 20% of the operators did not turn their keys proving that this job may be better delegated to a machine that will always "turn the key" when provided a correct code. As a result, all of the operators were replaced by WOPR. However, removing the humans from the loop got rid of a crucial fail-safe in the system.

This wasn't in the movie, but the removal of the silo operators in favor of WOPR could've paved way for a group of workers responsible for maintaining WOPR and making sure that there are no software bugs. Testers may have been able to find the backdoor "Joshua" that allowed Lightman to break into the system.

Joshua, is an artifical intelligence created by Dr. Falken to play games. It learned by repeatedly playing games to discover the most winning strategy. Lightman and Dr. Falken used this learning to their advantage by teaching Joshua that the only way to win in Global Thermonuclear War is to not play at all.

[1] YouTube, WarGames, 6 Jan. 2020, www.youtube.com/watch?v=HNLQ-O-Qx3Y&t=1779s&ab_channel=YouTubeMovies (20 Sept. 2021)