Using MIA Ping over your teammate.
I used to get really upset after I try my hardest to get a kill and my opponent put a single question mark in all chat. To me it's the ultimate disrespect, it lazily indicates that my play was so bad that my intentions weren't even clear. I took a long break from league of legends and coming back I see that people have begun using the "MIA" ping over your dead body. Recently sky mentioned in a video that every time you make a mistake you have to take shit in chat, but you can easily mute chat. I see the ping used like this about four times more often than I see it used as intended. If a tool is used this often to make your teammates feel awful then it should be removed. I use two caution pings down a river to indicate MIA anyway.
Sky video: https://www.youtube.com/watch?v=08m4nJMHMiU
