Just typing something and then not sending a message puts me out of order for about 5 minutes while I'm waiting if there is a message coming. And then another 10 minutes while I'm speculating what he could have wanted from me.
People do that?
Happens often enough that people start responding but then realize they don’t actually have anything useful to say right now (“never mind”).
There's that one guy who built a bot that automatically sends the typing signal back whenever it detects someone typing. Very funny prank.