There are also disadvantages to small group interaction. In some cases, one person can be just as or more effective than a group of people. Think about a situation in which a highly specialized skill or knowledge is needed to get something done.
This is strange to hear. I know there's these group think-tanks that come up with better results than many experts do because of the sheer amount of polled suggestions. sure, most of the suggestions could be rubbish, but if you have enough suggestions, one of them will make sense. Obviously people who detract from group discussions/don't do their part shouldn't be contributing anyway, just because of lack of interest, but sometimes bigger groups yield more fruit.