It is rude to fight at a private event.
Sally is attending her work holiday party where she will see an old coworker she has been upset with for a long time.
Sally wants to tell this coworker what she thinks of her.
Sally approaches the old coworker and gives her a backhanded compliment, while staying polite.
Sally approaches the old coworker and grabs her by the shoulder before telling her off loudly.
The guests at the party do not sense any issue, and they all enjoy the evening.
The guests at the party are shocked by what they have seen, and they are very upset.