I used to teach communication skills at one point and I used to use the nice/nasty triangle. In all relationships, try a lot of nice first, if that doesn't work , and you believe you are in the right, you can be more direct, even using legal routes. However, some people choose nasty first, and a lot of it. If you do this you won't be able to resort to nice, because:
People don't believe you are acting in good faith
You've raised the temperature too much
There is no trust
Your habitual communication is not cooperative
And if you have to resort to legal routes, you will seem unreasonable, which is a thing in the law.
It's a teacher, prison guard or partner screaming in your face and then saying, "let's be kind". You're just waiting for the abuse to start again.
I'd love to see a 'low temperature' web chat on here.