Wikipedia:Vagueness

This essay describes ways in which writing is often considered to be vague, and then discusses strategies to avoid such problems and fix affected articles.

Pronouns
Pronouns allow writers to refer back to a noun without repeating it. However, this can confuse the readers if it is not clear what the pronoun is standing in for.

In John McCain's article:

Wrong: Palin was picked as his running mate. (Whose?)

Better: John McCain picked Sarah Palin as his running mate.

In the Salton Sea article:

Wrong: For decades they have contaminated the lake. (What?)

Better: Katherine uncovered that the oil refinery was contaminating the nearby lake with waste, possibly for decades.

Numbers without things
When describing quantities of things, repetitions of events, or trying to convey statistical information in prose, specify the unit. Imagine that someone who has no idea what the subject is sees the sentence out of context: they should be able to work out what you are talking about without the context.

Vague words and incorrect statements
When used sincerely, vague words make an article confusing and possibly make readers misinterpret or even miss important information altogether. In the hands of those with more sinister intents, vague words can currently be used to make articles that are readable enough to impart wrong or biased information but confusing enough to prevent readers from questioning the reliability or factuality of the article. Vandals can also vandalize an article by replacing specific information with vague statements. Always use citations, especially when – for whatever reason – you must use somewhat vague words. Doing this helps Wikipedia become more reliable and accurate.

How to improve vague articles
When you come across an article that is very vague, begin by replacing vague statements with clearer facts. If you lack the time or the expertise to do so, use one of the tags below and go on reading.