Kill them with kindness?

...Okay, so more than 30% people from Scandinavia have confirmed that the qouete: Kill them with kindness, is one of the most meaningful & powerful sentence to always keep it in your mind.

But what does it really mean? I have asked both my family and friends and everybody is telling me diffrent things that I can’t really agree with.

Like: Imagen that somebody is yelling at you, instead of you yelling back you could just stand and smile and that will make them more angry.

But I feel if I would have done that to somebody I know, they would just step over me and counting to treat me bad?

What does ”kill them with kindness” mean for you? I am really trying to figure this out, so I would LOVE your respond even if it something that would not make any sense.

Sorry for my bad english I am from Denmark.