|This is an essay. It expresses the opinions and ideas of some Wikimedians but may not have wide support. This is not policy on Meta, but it may be a policy or guideline on other Wikimedia projects. Feel free to update this page as needed, or use the discussion page to propose major changes.|
There are some users that are disruptive across multiple Wikimedia projects. Sometimes it is because they are incompetent in certain areas (see WP:CIR, and no, do not go calling people incompetent). Other times it is because they are pure vandals. The one-strike rule prevents cross-wiki disruptive users from editing Wikimedia projects.
The one-strike rule is as follows: Users who have been disruptive on multiple Wikimedia projects violating policies may be blocked if they violate the policies of that specific project even once.
Remember, not all users are intentionally disruptive. The one-strike rule prevents even the most accidental or intentional disruption from occurring on Wikimedia projects.