Wikipedia:How Wikipedia notability works

Wikipedia's notability requirement is perhaps the most confusing of all core guidelines and policies. Rather than being truly defined in one place, wiki-notability has a defacto definition which is the end result of a complex wiki-notability ecosystem. This ecosystem consists of guidelines, established practices and values, venues and other pages and human decisionmaking. Decisions made in the name of Wikipedia notability also take into account other considerations which are not explicitly Wikipedia notability criteria. The system mostly works, but is very difficult to fully understand or explain, and also results in an unusually large amount of large unresolved questions. This also makes evolving or clarifying the guidelines very difficult. This essay intends to assist in that area by providing a framework that describes the status quo, and then reconciling and explaining the more confusing areas using that framework. It describes how it is and makes no assertion on whether or not that is how it should be.

Terminology
In this essay:
 * "Wiki-notability" refers to the entire wp:notability ecosystem
 * "WP:Notability" refers to that specific Wikipedia page
 * "Sourcing-GNG" refers to the sourcing-based criteria portion of the WP:Notability page
 * "SNG" refers to the subject-specific guidelines listed at WP:Notability, a common abbreviation derived from "special notability guidelines".

The ecosystem uses the decisionmaking process defined at How editing decisions are made, a process which is also used for other decisions.

Executive summary
The wiki-notability ecosystem is the main screening system for existence as a separate article. It does this by reviewing these criteria, taken together. "Taken together" means that all three criteria are weighed and weighted. Greatest weight is given to #1 (which is the sourcing-GNG) and GNG is also a gauge of #2 making it doubly influential. Under "taken together" a strong pass under #1/GNG alone is sufficient, #2 and #3 non-withstanding.
 * 1) Degree of availability of suitable sources from which to build an article
 * 2) Degree of importance, impact or prominence of the topic
 * 3) Degree of encyclopedic-ness of the topic. This goes beyond simple pass/fail under WP:not

An even shorter executive summary
The most influential criteria is GNG type sourcing, but these two items also matter:
 * How enclyclopedoic is the topic?
 * Real world notability

Mission and definition of Wiki-notability
The mission of wiki-notability is to screen topics for separate-article suitability based on the following qualities:
 * 1) Has or is projected or believed to have sourcing available from which build a suitable article. The measure of this is that there are sources of in-depth reliable objective coverage of the topic. Or that it is sufficiently sound to believe that such sourcing exists or will be created.
 * 2) Meets some degree of exclusivity (beyond meeting the "floor" requirement of not clearly violating wp:not) sufficiently to be allocated a separate article in an encyclopedia of the English Wikipedia's approximate size. For example, a size that may "only" grow to 20 million articles. These three main factors for this quality are considered jointly, with the greatest weight given to the first factor:
 * Existence or predicted existence of in-depth reliable objective coverage of the topic, sometimes weighted by the nature and prominence of the source. Note that this is a second use of sourcing as a measure, this time as a measure of the "#2" (above) quality. The sourcing-GNG is a guide, but sometimes that guide requires & receives calibration in specific topic areas. For example, areas that are coverage-heavy or coverage-light in proportion to that quality.
 * Degree of encyclopedic-ness including: by what degree did it exceed the minimum requirements of wp:not and and how closely does it align with the first of the Five pillars? So this consideration is a matter of degree beyond just meeting the lower bar of not clearly violating those criteria.
 * Degree and scale of real-world scale, prominence, recognition, impact and importance, weighted towards endurance of these qualities.

The in-practice definition of "Wiki-notability" is having a sufficient amount of the above qualities. Note that GNG type sourcing counts most heavily and twice.

So, GNG sourcing is an indicator of wp:notability beyond merely providing content to create an article from. This leads to two calibrations in the assessment process:
 * Larger scale and more prominent sources tent to count more heavily
 * Acknowledge that the "coverage to actual notability" ratio varies between fields. For example, in sports-related field coverage (in addition to providing coverage) is also created as a form of entertainment.  At the other extreme (such as academics) GNG type coverage is sparse in proportion to wp:notability.  To only a limited extent, the wp:notability recognizes and calibrates for this variance.

How wp:notability works: notes on confusing areas
The ecosystem uses the decisionmaking process defined at How editing decisions are made, a process which is also used for other decisions. In essence, each decision considers and weighs multiple factors.

The wiki-notability ecosystem includes core guidelines, various venues, important closely related pages, plus past traditions, decisions and practices. Due to the quantity of these important items and various other issues, the wiki-notability concept is vaguer and more dispersed in Wikipedia than others which are more contained within one policy or guideline.

The most-core notability guideline is WP:Notability. The first section / "lead" of the WP:notability guideline (plus a few paragraphs in the body) is actually a functionally separate meta-guideline covering both overall wiki-notability and Wikipedia's meta statement of the main criteria for existence of an article. For example, this portion gives Wp:not a prominent procedural place and defines the place SNG's (Special Notability Guidelines) have and defines which are official. The remainder of WP:notability is a sourcing-based criteria, often referred to as "GNG" or the "General Notability Guideline"; we'll call it the "sourcing-GNG". Thus the term "GNG" has two common meanings, either the latter, or the entire WP:Notability page.

Rather than being written worded as being authoritative criteria, the guidelines use vaguer, softer wording, in essence saying that they are merely indicators. The widspread usage of "presumed notable if...." indicates that such criteria are not absolute or permanent. They also have general principle type wording which generally includes deference to the sourcing-GNG, and indicates that they are mere predictors of having the sources that it requires. In Wikipedia, when there are debates or disputes, for better or for worse, operative wording (which has operative "teeth") rather than "principle" wording tends to have greater influence on the result, which tends to give specific SNG criteria extra influence on results even when GNG sourcing is used as the main criteria. Also, a few of the SNG's have wording which toughens the sourcing requirements of GNG. Finally, SNGs assist in judging the third criteria under quality #2.

Applying Wikipedia's rules is usually not a simple "black and white" situation. For example, one decision may be influenced by a multitude of policies, guidelines and objectives. The "fuzzy" Wikipedia decision-making system finds a way to make it all mostly work. Included in the system is discussions which weigh multiple factors (and assign different weights to each) in each decision. So the process is usually more like a neural net than a flowchart. This is particularly true with wiki-notability discussions.

When wiki-notability of an article topic is question, the substantive discussion on it usually occurs at the articles for deletion venue. When a certain type of topic has the same outcome a multitude of times, the outcome gets listed at Articles for deletion/Common outcomes. Since that page documents the results of the overall wiki-notability ecosystem, including consideration of currently undocumented considerations, it has a significant place in the wiki-notability ecosystem. But it is only an essay, and contains cautions to not quote it as if it were something more than that.

When the article might be an attempt commercial promotion, this may get weighed in the decision. It relates to "degree of enclyclopedicness" but also may be a quick indicator on where the listed sources represent an already maxed out search vs. just the tip of the source iceberg.

Does the sourcing-GNG reign supreme?
The short answer is that it is by far the strongest consideration but not the only one.

The sourcing-GNG has a role defined by the meta-guideline as one route to wp:notability, and is also featured prominently throughout the rest of the wp:notability ecosystem. For example, SNG's are generally worded to say that they are merely predictors of meeting sourcing-GNG type criteria. The sourcing-GNG defines principles that are used in judging both of the qualities described at the beginning of this essay. Also, in the ecosystem, there is little or no support to consider meeting a SNG to be a permanent bypass of meeting a GNG-type sourcing requirement. Finally, the WP:Notability page reflects a broader consensus than any other wp:notability page giving additional weight to everything on it including the sourcing-GNG. These roles give the sourcing-GNG the highest place of all wp:notability criteria, but "highest place" does not necessarily mean an absolute immediate requirement. Nor does that preclude other factors having some influence on wiki-notability determinations.

Is our practice on geographic inhabited places an exception to the framework described here?
No. Regarding "quality #1", it has in essence been determined that in these cases a small article may be of "suitable size"; this is influenced by inclusion of Wikipedia's gazetteer function in the Five pillars. It has also been determined that those covered under the SNG meet quality #2, including being particularly strong at being encyclopedic topics. The Notability (geographic features) SNG and its status as being widely accepted document these, along with a further recording of this at Articles for deletion/Common outcomes.

Since WP:NCORP sets tougher sourcing standards, does it override or conflict with the sourcing-based GNG route in?
No. On the face of it this conflicts with the highest-authority meta-guideline at the beginning of WP:Notability which says that meeting the sourcing-based GNG is sufficient. But the meta-guideline also acknowledges that the SNG's may calibrate the sourcing-GNG in a way that toughens it in specific areas.

Summary of relationship to WP:Not and the geographic item on WP:Five pillars
To some extent, WP:Not and the geographic item on WP:Five pillars are a part of the wiki-notability ecosystem.....the "notability" ecosystem weighs them in decisions.