I was once being followed and harassed by a woman. I told her to “stay the fuck out of my life”.
Nothing came of it, but when I asked a lawyer about getting a restraining order against her, he told me that she actually had grounds to get an order against me, specifically because I had used the word “fuck” when I said that to her. That word, he said, could be considered evidence in a hearing that I was dangerous to her.
So basically, my primary reason to stop cursing is to avoid triggering special rules (not only legal, but corporate rules as well) that are activated by a person who says those key words.