Another way editors can add information to an article is by finding a source for existing unsourced material. This is especially true if you come across statements that are potentially controversial. You do not need to be the person who added the information to add a source and citation for it.
== Wikipedia is a work in progress: perfection is not required ==
''Perfection is not required'': [[WP:WIP|Wikipedia is a work in progress]]. Collaborative editing means that incomplete or poorly written first drafts can evolve over time into excellent articles. Even poor articles, if they can be improved, are welcome. For instance, one person may start an article with an overview of a subject or a few random facts. Another may help standardize the article's formatting, or have additional facts and figures or a graphic to add. Yet another may bring better [[WP:NPOV|balance]] to the views represented in the article, and perform fact-checking and [[WP:CITE|sourcing]] to existing content. At any point during this process, the article may become disorganized or contain substandard writing.