I suppose my observation is primarily about creating a professional image in the classroom, but it also seems to affect teacher/student rapport and the nature of the teacher/student relationship.
Over the years, I've found that individual instructors tend to have very strong preferences about whether or not they would allow students to address them by first name. Some instructors only allow students to address them by their professional title (e.g., Dr. So-and-so) or standard formal address (e.g., Mr. or Mrs. So-and-so).
My last name can be difficult to pronounce for some students, so on the first day of class I… >>>