How do you explain barriers to effective communication?

Introduction 2. Organisational Barriers 3. policies 3.status and position 4. semantic barriers 5.Badly expressed message 6. Imperfect translation 7. Unclarified assumptions 8. Application of jargon's 9. Barriers among superiors 10. Regards and gratefulness 11. Excessive use of Authority 12. proper channel syndrome 13.Prejudice 14. Disbelief 15. Sycophant syndrome