I have some great memories with some of my teachers. Some because they were incredibly kind and encouraging. Others because they were just very good teachers and taught me a great deal. Others because they had a great sense of humour.
I've also had not so great tutors. Boring teachers, complacent teachers, others who constantly went off topic so, you really felt like you were learning nothing relevant. Teachers that got incredibly angry. All sorts.
I'm not sure even the worst expereiences were deliberately malicious. I don't have any deep scars as such from education.
That said, they make an incredible difference to our lives. They can absolutely make or break when it comes to confidence building. Especially with shy, unconfident children. I suppose that's why I've always prefered the kind, supportive approach. Not to say we shouldn't be criticized but, I think a balance is important not to totally decimate a person's self worth before they even begin!
The outside world is incredibly tough. Maybe it's good to build up strength for that- toughen people up. Still- go too far and they can feel as if they've failed before they've even tried. The best approach I found was teachers that tried to build people up, not tear them down.