Because some such as Jehovah's Witnesses are following what Jesus Christ instituted for his disciples to do and that was to share the "good news about God's Kingdom" with their fellow man. Jesus himself took the lead in sharing his heavenly Father's Word with others (John 17:6,7,8). Also Jehovah's Witnesses do not force their religion on others. They respect peoples choices to have their own faith and beliefs. If a person declines to hear God's message they keep seeking out "deserving ones"
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