Last conference of the night I had a parent come in exhausted, dejected, and angry. He was surprised to learn that his child was not only doing well in my class, but participating and asking questions when he needed help. Apparently I'm the only class he's doing well in and his parent was not expecting to get a good report, especially since all the previous reports were so negative.
He left with a ray of hope and said that while he was planning on taking his child to task for his behavior/performance in the other classes, he was going to praise him for his work in mine. No interaction should be 100% negative. This is often why I'd think the parents that you REALLY need to see don't come, don't take calls, and don't show in interest. Who would want to be told they are a bad parent all the time? Who wants to sit and listen to people tell you that your kid is stupid and ill behaved? Nobody. Even if you have 90% bad things to say, there's something good you can say even if it's "well, she shows up...not every kid does that." Is that good? Not really, but it's a start. We can build from there.
Dallas Parent Teacher Conferences Part 1