I never went to university, but in high school I had two different teachers, and one was hundreds of times better than the other. I am not really sure how tea

I never went to university, but in high school I had two different teachers, and one was hundreds of times better than the other. I am not really sure how teachers get hired, how they are interviewed and assessed, but the system is clearly not working; particularly in subjects that the learning curve is not a curve (like math, or physics or cs)