Wikipedia:Notability is not a matter of opinion

On Wikipedia there are set policies and guidelines regarding notability and verifiability; when an article fails to meet these criteria, it is generally nominated for deletion via proposed deletion or Articles for Deletion. Normally this results in a clean consensus to delete (assuming of course that the nomination and discussion was valid); however, there are cases when an editor, often someone new to Wikipedia, tries to defend an article because they do not understand why the article was nominated for deletion.

For example, assume the article Popular Awesome X, which covers a video game, is nominated for deletion because it fails to meet notability guidelines. An inexperienced editor who is in some way a fan of the game may see the AfD tag and panic, deciding to rush to the article's aid with something like: Strong keep this is clearly an important game and its really popular. All my best friends play and love this game. PAXfan01 (talk) 96:00 am, Sometime (UTC+i) However, this argument holds no weight since:
 * It is not supported by any policies, guidelines or precedents;
 * It does not represent a neutral point of view;
 * It demonstrates a lack of research into the subject, and may be a sign that the article does not meet the verifiability criteria;
 * It does not actually establish notability, and may even serve to demonstrate a lack of such;
 * It is specifically listed as one to avoid in deletion discussions and does more harm to your cause than good.

If you are new to Wikipedia, or you are otherwise unfamiliar with its deletion policy, and you wish to participate in a deletion discussion, please keep in mind that notability is not a matter of opinion. Arguments for keeping the article should be supported by reasonable evidence such as reliable sources, not whatever you believe. If you cannot find any suitable references after a thorough Google search, then you may tag the article for rescue if you are certain the topic is notable.

If you do find references to support notability of the subject, you are not limited to listing them in your argument; even during the AfD process, you are welcome and encouraged to add your references as citations in the article itself. This demonstrates your willingness to improve and contribute to Wikipedia, and can further show that the subject is indeed notable and does meet Wikipedia's criteria for inclusion. Most importantly, while listing your citations may result in the article being kept, adding them to the article is more effective for your cause as it helps to explain how the topic is notable; in addition, it saves other editors the trouble of having to look for references afterwards, and does more to improve the article than a debate that is eventually forgotten and overlooked.

Above all else, try not to get worked up over a deletion debate; after all, Wikipedia isn't actually that important.

Other things notability is not
From a more philosophical perspective, notability is also perhaps not objective; necessarily permanent; judged in isolation; nor based on merit; these points are covered in detail at the essay WP:What notability is not. It is also said that notability is not a level playing field. From a policy standpoint, notability is also neither relevance nor reliability.