I believe the most common things the admin of many Wikias should not do is gloat that they are admin when they are obviously wrong or just being unreasonable because on some Wikias if people constantly disagree with a pages information almost ever week about a page I believe the Wikia should change because without the necessary members the Wikia surely will die and people will probably create their own Wikia that would probably be better than the others because multiple Wikias like the Naruto Wikia ,Bleach Wikia , and One Piece Wikia can change things that are wrong through researching the series fully and then apply this logic into fixing the errors where most Wikia's would use the "I am the admin so my word is law and so is my opinion." which is annoying and bluntly immature because an Admin should know the series they are editing for not the other way around with giving false information because a Wikia should be factual unless it's fan fiction type Wikia.

So what are the most common things that you think an admin of a Wikia should not do?