There's a big difference between talking 1-1 in a nice office with a teenager, to teaching in a classroom 1-30. Kids can be absolutely lovely 1-1 and then, in any sort of public environment, with friends or in the classroom, exhibit damaging behaviours. But behaviour matters everywhere. So if you only ever see the former, you won't understand the latter, and your views on how things should be will be coloured by that.