Think about what slaves do. They work for the master and they humbly work hard and if they don't they'll get punished. A slave is lower in rank than any others. Slaves do not enjoy prominence. They do not have special insight or knowledge. They are simply lowly slaves.
But in Watchtower World, a simple illustration of faithfulness vs. unfaithfulness becomes the cornerstone of their doctrine. Originally, the followers of C.T. Russell whispered he was that Slave or Faithful Steward. Eventually, Bible Students viewed Russell as "The Wise Servant" until J.F. Rutherford decided otherwise, years later. The consecrated bride of Christ was that Slave but in reality he formulated the Society as the Slave that gave food at the proper time. Then it morphed into The Governing Body but technically it has been all anointed ones on earth at any given time. Baloney! The GB make all the decisions and the result is the mythical "Slave Class".
Everyone is supposed to "trust" the Slave. "The Slave (Mother) knows best". "Obey The Slave".
For God's sakes, it's a "slave" not an owner. Only in Watchtower Land!