From time to time, someone comes to my talk page to ask why I reverted a particular edit, or why I used rollback on an edit that did not seem to be vandalism.
On principle, I do not use rollback for reverts that are part of a content dispute with an editor I disagree with. I use rollback for:
- vandalism;
- edits (usually from anons) that may not be intended as vandalism, but that completely messed up the format of a page;
- harassment on user talk pages;
- edits from users that have been banned.
Although it may seem unjust, it is inevitable that doubtful edits from anonymous contributors will be treated as though they are vandalism. If a registered user adds information to an article, and another users doubts the accuracy of the information, he can go to the talk page of the user who added it, and ask for more information. Or he can look through that users other contributions. An anonymous user may not be using the same IP the next day, so messages to IP talk pages could be a waste of time.
Users who have been banned from Wikipedia are not allowed to make any edits here. If they ignore their ban, their edits may be reverted by any Wikipedian. In such cases, some of the edits may be harmless, while others are extremly offensive. I do not revert blindly, so it is extremely unlikely that I will re-introduce spelling errors or previous vandalism. In many cases the user page or talk page of the editor that I have reverted will have information stating that this is a banned user. See also here.
If I find vandalism from a user, or, more often, from an IP, I look at that person's contributions, and often find more vandalism. Knowing that an IP can be used by completely different people, I do not automatically revert edits made on 27 May from an IP that vandalized on 14 June. But if several edits are made in close succession, I might check one or two for vandalism, and then hit rollback for all the others without looking. If I do look, and am unsure, I might put "Unsure, but rv because other edits made from this IP around the same time were vandalism" in the edit summary.
I sometimes find vandalism because an article on my watchlist is vandalized, and I then look at the contributions of the editor who vandalized it. I also look for vandalism by checking:
- Editors recently reverted by Tawkerbot2, Tawkerbot4, and AntiVandalBot
To sum up, if I have rolled back an edit, and there seems to be no explanation for it, it is either an edit from a banned user (and information will be available on the user page or talk page), or from an IP that had engaged in vandalism around the same time (which can be checked by clicking on contributions from that IP). If it does not fall into one of those two categories, then it is an error, for which I apologize.