I have had friends fail to communicate in astounding ways. Once, four of us were planning to go somewhere. A friend suggested somewhere else, I and my other friend agreed, but the fourth friend was not presnet. I told my first friend to tell the one person who was not present about the change in plans. He asks why... I tell him, well, the other guy isn't going to know we changed plans because he isn't here.
Basic communication goes a long way.