Wikipedia:DENY

This glorification of vandalism through infamy encourages Internet memes through reinforcement, where users imitate notorious or unique vandalism methods for amusement, to share in the infamy, or for the thrill of defying authority and/or interfering in other users' work. Denying recognition and infamy neutralizes common primary motivators for vandalism and disruption.

Some material is still going to be valuable in dealing with vandalism, so this is not about pretending vandalism does not exist. Information on vandalism should be critically appraised for its genuine value, and if that value outweighs any detriment from the publicity of that vandal/vandalism. Stating that a certain individual is involved in very obvious vandalism probably does not enable any better recognition or response to that vandalism, it merely adds to the legend of a specific vandal. On the other hand, documenting a new form of vandalism in a neutral manner like ensures a suitable awareness of that vandalism's existence.

If you see information pages about vandals or vandalism that you think have no practical purpose,

User pages of indefinitely blocked users (except sockpuppets and banned users) that have no practical purpose can be nominated for deletion as such after a short while.Remember that this is not a criterion for speedy deletion, unless the page is pure vandalism, or a personal attack.

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