Lack of classroom management skills makes a bad teacher, as does a lack of knowledge in the subject being taught. Issues with professionalism, motivation and organization also contribute to the development of a bad teacher.
Ineffective classroom management is a hallmark of bad teaching. No matter how good a teacher is in every other area, she must practice good classroom management to be successful. Excellent classroom management entails establishing processes, expectations and consequences right from the first day of class. Teachers who are inconsistent with expectations and who try to be students' friends practice bad classroom management and leave themselves open to students taking over their classes.
Many bad teachers do not know enough about the subject or subjects they teach. To avoid this problem, teachers must study lesson plans and course materials before presenting the information to the class. Otherwise, a teacher may risk losing her credibility with students and administrators.
Subpar judgment also makes a bad teacher because a teacher must be able to prioritize and keep her cool in a crisis.
Bad people skills also lead to bad teachers. If a teacher cannot connect well with other teachers, the administration, students and parents, she cannot teach material effectively.