Several times in the recent past I have written an email to a single person asking them a question. They replied to my question, but in their reply they carbon copied (cc'd) several other people. In one instance the cc'd person was relevant. In another instance the cc'd people were most definitely not relevant, and I was surprised to find the responder write, "We discussed your question and decided..."
I understand people are trying to be helpful, but this is getting a bit ridiculous.
When I telephone someone, there is usually a social contract that the telephone call is just between the two of us unless otherwise specified. Somehow this has been lost in email. (Maybe it was never there in the first place?)
Several lawyer friends have told me they don't conduct any business or send anything remotely important over email - they do everything in person or over the phone. "It's not discoverable", they say.
Despite having the typical Computer Scientist's dislike of telephone conversations, I am now beginning to appreciate their value.