Good Discussion And Bad Discussion(ASP assignment)

I watched the movie that show what good discussion is and what not is.
In the movie of bad discussion some of the girls didn't concentrate(playing with them hair, not looking at who was speaking) or interrupted during another was saying opinions and then a serious quarrel broke out. However, there was also who couldn't say anything.
On the other hand, in the movie of good discussion everyone look at who was speaking, listened to other person's idea until stopping saying and sometimes nodded.There was a good leader, who gave everyone chances to say something in order. Moreover, if someone wanted to oppose they were polite, for example, saying "Of course it's right, but I think ~."
Until watched these movies, I thought that for good discussion having own opinion firmly and speaking about it actively is most important, but now I think what most important is not hurting other persons feelings, in other words, being polite even when I can't agree with other person's ideas. Discussion is not a verbal conflict, so it's goal is not criticizing others but generating new good ideas by cooperating with other persons.