Good or bad teachers or students?
Let's leave apart qualifications, experience, wants and these things. Because if a teacher is not qualified or doesn't know the subject, this person is always going to be a bad professional, in any area. And if a student doesn't want to or feel like studying, they are not going to learn anything.
All teachers are valid as well as all students want to learn. If we fail as teachers or students, it could be, perhaps, because we haven't found the system adapted to our needs, or what we want to learn.
- Give your teacher a chance to show how good he or she is, and let your student time to improve and get confidence with the language, so you will see their progression.
- Find the teacher who fulfill your needs in order to get what you want to learn. And listen to your student to know what they are looking for.
I am a bilingual English teacher. Many students when they know I am native Spanish don't know if I am going to be good enough for them. But I can tell you, after a class with me, they know they are going to learn English and improve their level. They notice I know what I am doing and like it a lot, make them participate in their own improvement and consequently getting their goal.