According to Osho, people preach because they fear their own ignorance and choose the easy escape of borrowed knowledge over the arduous journey of self-knowing. Quoting scriptures and ready-made answers flatters the ego and provides a counterfeit certainty. Preaching becomes an exhibition to persuade themselves they 'know,' so they advise unasked, irrespective of listener or context.
People preach because it feels easier and smarter to repeat what they’ve heard than to do the hard work of truly understanding.