As writers, we are told to choose our words carefully. Every word used must have purpose. We pick through our sorted list of vocabulary with dauntless effort. It's a lesson non-writers should use when they speak.
Would you allow me a moment of back story? My daughter, she's 10, likes to make crafts made from duck tape. (Yes, "duck".) It's like duct tape, but it's colorful and full of patterns. She makes headbands with big bows on them. It's wonderful and she wears them proudly. Until an adult decided not to be careful with her words. An adult, she is not related to, but is forced to see once a week. And not forced by me! Because if I had my say, this lady would be gone. This adult decided to tell her that she was a baby for wearing her bow. (I had a conversation with this person, but that's not my point today.)
She won't wear those bows anymore. In one sentence, that adult slashed her self-confidence. And it won't matter how much I tell her it's okay to be an individual and she should be proud of herself. It won't matter now, anyway. Some day, but not today. Today, that one sentence has more power than a thousand of mine.
When I'm writing dialogue between Gabriel and Owen, I think, "how will Gabriel react if Owen says that?" Shouldn't everyone mutter those words to themselves before they allow their lips to open and the words to tumble out? I can delete dialogue that doesn't work. You can't take your words back once you've said them. Even if you've asked for forgiveness, your words have left their mark.
One sentence can be very powerful. From: "Will you marry me?" "Have a nice day." "Thank you." To: "You're a baby for wearing that bow." "Why would anyone like you?" "Why do you dress like that?"
One sentence. Tiny words that left alone mean nothing. But pieced together in a certain way have as much power as an explosion. Choose wisely.