"You can't control other people's tempers, but you can keep a cool head"

This is one of the loading screen tips, and it has two meanings. The first undoubtedly is that you should try your best to stay calm when things aren't going well. But the second is that you should be mature enough to understand no one is attacking you when they aren't as calm.

The report system shouldn't be used to steal paid content from people who use the chat function to vent frustration. You aren't keeping a cool head if you're so angered/upset by some random stranger's comment that you're bad at your champion that you can't own up to your performance, and report them out of spite because the automated system doesn't care about what's right.

You can keep a cool head, so don't act it isn't your job to use the mute button when you can't handle player vs player interactions.