Teaching is our job. Students, their families, and the public all expect that whatever else goes on at a university, teaching stands at the center. This is why they pay fees and make donations, which go toward paying instructors and staff. Teaching develops relationships. Some of the most profound and long-lasting friendships are between instructors and students.
Teaching produces future researchers.
The beginners we teach today may be award-winning academics tomorrow. Teaching produces educated people. College instructors, after all, have as much to complain about in the state of the world as anyone else. Usually, people who went to college. Teaching energizes research.