I am often surprised at how people handle their communications with others. I don’t understand why they don’t make it more important.
For example, I once was asked to have two people shadow me for a consulting job. When I asked if they had spoken to the manager they said they would contact them. I reached out to the manager and let them know so that it wouldn’t be a surprise. I wouldn’t want to be a manager and suddenly two people are in a meeting that I don’t know anything about. It would make me look incompetent.

One of the things that I have learned in life is to overcommunicate. I had a boss tell me that I overcommunicate. He said I worry about closing the loop and that people can find me annoying by following up for answers. I said I will not follow up and he was happy. I found this instruction confusing, but if that makes him happy, I am happy to do what makes my bosses happy.
Interestingly some other coworkers have appreciated when I have overcommunicated with them. One said that she doesn’t think that overcommunication is possible, and appreciates that I let her know anything that might be helpful for the client. I have had more people appreciate that I follow up and double-check than not, so I guess I will continue to overcommunicate in the future.
Now of course there is an annoying level. You don’t want to insult people’s intelligence, waste time, or confuse people. I only follow up when there is an action item that needs to be done, or something is left unclear. I don’t want to waste my time or anyone else’s. However, I have noticed in most companies that the unclear and grey areas don’t get worked on because no one wants to take responsibility. If you make something clear, then things are more efficient.
Well, that’s just my two cents. I could be wrong.