Typically this is notable when a statement is made, and then immediately taken back.
Example 1: John was a good looking man, at least to most, who knew how to get what he wanted.
Example 2: Stacy walked down the black corridor, which was more of a dark gray.
Statements like these have a tendency to: a) cause confusion, and b) add very little to the narrative. Is John good looking or not? Is the corridor black or gray? Just tell us, Ms. Narrator.
Instead of spending time going back and forth on one detail, pick one and describe it. Decide John is good looking and describe the features that make him such. Decide the corridor is black and describe what that means.
Side note: I'm talking about non-first-person narrative. First-person narrative is character driven narrative, so doubt in the narrative would be totally subjective to the character you are writing.
Narrative that struggles with the details is really an indication of the author's internal struggle
I really believe that when the narrative struggles with the details, it's an indication that the author is struggling to decide herself. Narrative that can be confident, to-the-point, and not beat around the bush has the potential to create the vision the author wants.
You, Author, are telling the story. So tell it. Don't be that guy trying to tell someone about something that happened once who struggles over what day of the week it was when something happened...
"So, it was Wednesday... wait, no, it might have been Thursday. Yeah, it was Thursday, because we had our product management meeting that day. Yeah, so, I was sitting here, and she was sitting there. No wait, I was sitting here, and that was the week we postponed the product management meeting because of Stacy's baby shower. That means it was Friday, and I do reporting on Friday, so I was probably in my office. Well, anyway, it doesn't really matter when or where it happened. But I'm telling you, it was hilarious."
And it wouldn't be appropriate discussing confidence without Julie Andrews.
What do you think? Should narrative be confident? Have you noticed this in your writing? Have you never thought of it before? Sound off in the comments.