People who just incorrectly use/don't look at your status on teams, or just call you or interrupt you out of the blue with no like "hey got a sec, I really need this but it can wait until you're finished" IM sort of thing if it is important. Rarely, if ever, do you need to call someone out of some sense of emergency for work.
Like getting IM'd about trivial/unnecessary things during the middle of a call, or just ignoring the "red" or "presenting" icons for said trivial or unimportant stuff that can either wait or just send me an email to answer at my convenience. It's distracting and inconsiderate.
It usually always ends up being the same type of person, one who poorly plans their work, or doesn't care or think about how their actions impede on another person's time. If I need to IM someone I always try to lead with a "when you got time" or similar so I can sort of "reserve" time to talk to you, but also acknowledging that hey, you probably got something going on at that moment, so don't feel like you gotta drop what you're doing to come take care of lil ol me.