Or any other medium in which your name is already visible in another way (Facebook messages, forum posts, etc.), why do they still feel the need to sign with their name at the end of the message? I've always found it weird, and you'd think people would realise it's truly unnecessary! The only way I see it is from people that were used to doing it when, say, writing hand written letters... Or they still see it as a formal or polite way to end a message, a "signature". To be honest, I don't see the need for it, and it kind of irks me.