[llvm] [Docs] Update Maintainer in Developer Policy (PR #154687)

[Aaron Ballman via llvm-commits]

================
@@ -141,57 +141,79 @@ products.
 Maintainers are those volunteers; they are regular contributors who volunteer
 to take on additional community responsibilities beyond code contributions.
 Community members can find active and inactive maintainers for a project in the
-``Maintainers.rst`` file at the root directory of the individual project.
-
-Maintainers are volunteering to take on the following shared responsibilities
-within an area of a project:
-
-* ensure that commits receive high-quality review, either by the maintainer
-  or by someone else,
-* help to confirm and comment on issues,
-* mediate code review disagreements through collaboration with other
-  maintainers (and other reviewers) to come to a consensus on how best to
-  proceed with disputed changes,
-* actively engage with relevant RFCs,
-* aid release managers with backporting and other release-related
-  activities,
-* be a point of contact for contributors who need help (answering questions
-  on Discord/Discourse or holding office hours).
+``Maintainers.md`` file at the root directory of the individual project.
+
+Maintainers are volunteering to take on shared responsibilities
+within an area of a project, not to exert power through that status.
+Actions and opinions of maintainers have equal weight to those of other contributors.
+Conflicts are resolved by the area teams (defined in `LP0004
+<https://github.com/llvm/llvm-www/blob/main/proposals/LP0004-project-governance.md>`_).
+
+The main responsibilities of a maintainer are to:
+* **Code Review**: ensure that commits receive high-quality review, either by the
+maintainer or by someone else,
+* **RFC Engagement**: actively engage with relevant RFCs, provide feedback, and
+help drive discussions to conclusion,
+* **Mediation**: mediate code review and RFC disagreements through collaboration
+with other maintainers (and other reviewers) to come to a consensus on how best
+to proceed with disputed changes, by finding a common ground,
+* **Triage**: help to confirm and comment on issues, aid release managers with
+backporting and other release-related activities,
+* **Point of Contact**: be a contact for contributors who need help (answering questions
+on Discord/Discourse or holding office hours),
+* **Behaviour**: ensuring that they, and the community members they interact with,
+abide by the :ref:`LLVM Community Code of Conduct`.
 
 Each top-level project in the monorepo will specify one or more
-lead maintainers who are responsible for ensuring community needs are
-met for that project. This role is like any other maintainer role,
-except the responsibilities span the project rather than a limited area
-within the project. If you cannot reach a maintainer or don't know which
-maintainer to reach out to, a lead maintainer is always a good choice
-to reach out to. If a project has no active lead maintainers, it may be a
+**lead maintainers** who are responsible for ensuring community needs are
+met for that project.
+
+This role is like any other maintainer role, except the responsibilities
+span the project rather than a limited area within the project.
+The hierarchy creates clear points of contact for contributors, where local
+maintainers should be contacted first.
+If you cannot reach a maintainer or don't know which
+maintainer to reach out to, a lead maintainer is always a good choice.
+
+Lead maintainers do not have additional privileges over other maintainers,
+for example overruling another maintainer's decision if consensus has been reached.
+They also don't need to know _everything_ that happens in the project.
+Having multiple lead maintainers can help cover all areas with reasonable depth,
+as well as allow for better coverage and response times.
+
+If a project has no active lead maintainers, it may be a
 reasonable candidate for removal from the monorepo. A discussion should be
-started on Discourse to find a new, active lead maintainer or whether the
+started on Discourse to find new, active lead maintainers or whether the
 project should be discontinued.
 
-All contributors with commit access to the LLVM Project are eligible to be a
-maintainer. However, we are looking for people who can commit to:
+All contributors with commit access to the LLVM Project are **eligible** to be a
+maintainer. However, we are looking for people who can commit to engaging in
+the responsibilities above consistently for at least three months in the previous
+6 months.
----------------
AaronBallman wrote:

```suggestion
six months.
```

https://github.com/llvm/llvm-project/pull/154687