I try to avoid being normative when I can help it. I forget when I started implementing Positivity Over Normativity, though it may have been upon reading Milton Friedman’s Methodology of Positive Economics. (Side note: positive = “the way things are”, normative = “the way things ought to be”).
There is a difference between describing something (“The man is wearing a blue shirt”) and valuing that something (“The man’s blue shirt is hideous”). Sometimes the line between the two may blur as a would-be observer convolves description and prescription. The essence, I think, is in stating or implying that a certain something is “good” or “bad”. For example, “It’s bad to drive around with underinflated tires” pales in comparison to “You can improve your gas mileage by up to 20% by fully inflating your tires”. In this case, you’re still implicating something in a value judgment, but by being specific you shift it onto improved gas mileage and away from the person’s poor automobile maintenance abilities.
I can think of two benefits from separating the positive from the normative. First, for those of us who try to think like scientists, it makes it much easier to reason about the world objectively, without having emotion cloud your judgment. Second, in going about your daily life, you will be less likely to needlessly offend others because of a clash of beliefs.
When you do your best to describe what is, you don’t get your emotions tied up in your perception of the world. When someone challenges your world view, you can adapt to it more easily. After all, an observation is much less a reflection of who you are than a value judgement is.