I recently worked with a career ESL teacher--Africa, Middle East, China--with credentials up the wazoo. On paper he is the ideal ESL teacher; in the classroom, his students are bored out of their skulls. Somewhere along the way he forgot how to be interesting. He's become reliant on posters, pictures, songs, just entertaining whoever it is sitting in desks in front of him.
This was at a language training center, and we would occasionally sit in on each others' classes. This gentleman never realised how dull things were as he never made eye contact.
I'm sure some students responded to this type of teaching, but the few return students from his classes would request a different teacher.
At the end of each course, students were requested to write an evaluation of the course and the teacher (generally used for advertising purposes!) He was always surprised when he would recive almost no feedback, just really general stuff, if anything. "Thanks" "Helpful" "Bye bye"
An evaluation needs to be both quantitative (numeric/objective) and qualitative (subjective.)Some people feel better at one over the other.