What you all said are not wrong, once you get to a certain point (40+ study score) your teacher can't do much to make you get better scores. Honestly some teachers are just plain bad, their teaching style may not suit every student, but if they don't put in the effort or care that just makes things turn into hell. Students are quite good judges on how a teacher does their jobs, most students will have good teachers, but a few bad ones. Hard work matters, but I am a strong believer that having a good teacher matters too, imagine having to self teach yourself everything ya know. I think it matters for certain subjects and having the foundation knowledge, once you have the knowledge you can just apply it elsewhere. Luckily for me a lot of subjects I am doing I can teach myself or go tutoring. Any teacher can be a great teacher, but not every student can be a good student.