Imagine you sat down and started reading a story that opened like this.
"What are those people doing out here?"
"I don't know."
Poppy sighed and ran a hand through her hair. The woman was very old. Her sister took off her scarf and went inside.
"How many days until Wind Set Day?" the prophetess asked.
"Four, maybe five, perhaps," she said.
How many people are in the story? Two? Four? What's the setting? Since someone goes inside, we can assume the characters are outside of something, so they are probably outdoors, but we don't know for sure. And what does the sister go inside of? A house? A store? A box? What kind? What's "Wind Set Day"?
These are all things we can guess at, but we can't really get a picture of what is going on. It's
vague. Unfortunately a lot of unpublished stories start this way. Later in this post, I'll go more into why new writers often make the mistake of starting like this and exactly
how it works to create a problem. (And yes, of course, all rules are made to be broken).
Vague writing is like this picture. Its blurry. Unfocused. As a reader, we can't really tell what is going on.
While "vague" and "ambiguous" are often considered synonyms, in a lot of places in the writing world, they don't mean the same thing.
"Vague" deals with the story being out of focus and vapory. It's not quite anything.
"Ambiguity" happens when something in the story could mean
multiple things--supported by evidence.