If you spend more than a minute with a good search engine, you can find dozens of explanations of just about any topic. Written articles, blog posts, podcasts, videos, books, slides, and infographics are just some of the many formats.
Yet when a teacher sits down to create lesson plans, the beginning is always Lecture Notes. The teacher presumes that before engaging with the topic, the students need him to explain it as only he can. When the teacher spends all of class time lecturing, she makes the implicit statement that the myriad of explanations on the internet are inferior to her own.
Is this pride? Is it fear? Perhaps teachers are afraid that if they aren’t lecturing, they aren’t needed anymore.
Teachers are(can be) much more than content delivery machines.