I have a friend who used to always put "Mark" and only "Mark" in the subject line of emails to me. It vaguely bugged me but I never told him to stop. Then I found out he did it to a mutual friend and she told me it really freaked her out and she told him to stop. She said having email with nothing but her first name as the subject made it seem like the message was going to have ominous news and she was loathe to open it.
In as essay for The Outline, Casey Johnston shares a similar experience: a boss who slacked "hi!" and only "hi!" Johnstone thought this meant she was about to be fired.
"Hi" implies "I need to have a full conversation with you that you're going to be present for," which is never good. Once I respond, if she responds to my response fast enough, I can't theoretically pretend to not have seen what she just said, because I was literally physically JUST there, responding; no one responds and then immediately logs off. Once I respond, she has me, but I don't know what for. It's like she has laid a trap that is very obviously a trap that I have to now just walk into knowing I'm about to get lit up for something. Except that I don't, really, because all she said was "hi!"
All she wanted was for me to fix a misspelling of a source's name in a piece. So I'm sorry, Erika, that I didn't punctually respond to your "hi," I was very busy having a heart attack.
If I got slacked "hi!" I wouldn't mind. Getting a "hi" without an exclamation point would seem like bad news was about to come, though.
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