One's word is his bond; so do you complete what you say? Or do you tell lies? Some people lie all day long and they are so good at it, they can smile and cough at the same time. Pro 14:5. Let us not be champion liars, but people who only speak if able to deliver what is promised. Pro 30:8.
Everything that comes out of the mouth will fall on the ears of someone who will be relying upon what has been spoken. And just that fact alone should make everyone determined to make good on what is spoken.
If you don't mean it, don't say it and you won't get in trouble for it. Eccl 5:1-5.
There is just too much of this nonsense going on and too many ruined people walking around because of it. Pro 29:12. Zech 10:2. Ez 13:22. Jer 29:31.