For me, it has to be when people move things, and then don't move them back to their original place. I find it incredibly annoying, and forces me to go out of my way to properly place the things back, I also get mad.
[spoiler][b][i][u]KUPO!!![/u][/i][/b][/spoiler]
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When people won't do simple things I ask of them. Like I'll be moving a 20 pound box and ask someone that isn't doing anything to grab my water bottle and they'll just say no and keep playing on my phone. Or when some asks me to do something for them and they don't say thank you. (This is fine if I do it without them knowing but if they ask they had better thank me)