One evening, after a frustrating chat with his boss, Jason Bauman sent an email to a co-worker. He wrote that his supervisor never praised him, only criticized, and said he found this frustrating.

He went on for several hundred words. Mr. Bauman, the manager of a cellphone store at the time, complained that his boss was bad at his job. He said the man was jealous because he made less money than his employees. He insisted his boss had no right to give him what he called “a hard time.”

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