Adminship on the English Wikipedia was originally no big deal, and is ideally supposed to be given to "anyone who has been an active and regular Wikipedia contributor for a while, is familiar with and respects Wikipedia policy, and is generally a known and trusted member of the community." Times have changed, to an extent, and the current standards people use to support or oppose someone for the mop and bucket are varied and variegated.
Personally, I feel that the candidate (in descending order of importance):
- must be able to converse clearly and civilly on talk pages and discussions across the wiki. This is my strongest criterion, and is non-negotiable; note that I did not say they must be a en-5/en-N speaker.
- should have solid answers to the obligatory questions, and most non-nonsensical optional questions posed. I prefer candidate interaction, including responding to statements made during the discussion or in opposition.
- should have some edits in the following namespaces: Main, Talk, Wikipedia, Wikipedia_talk, User_talk. Discrepancies in the number of mainspace edits compared to others will be taken into account for "specialized" types of admins.
- must do more than vandal-whacking. New Pages Patrol, Recent Changes Patrol, AWB, and related automation tools have made overall edit counts largely irrelevant. I want to see that you have the ability to utilize the knowledge and familiarity you have with Wikipedia's policies, guidelines, and customs to help the project, not how many times you can click a mouse in an hour.
- must have a "good" edit summary usage percentage in articlespace; this is vital to smooth functioning of the project, as page loads to check unknown edits take up valuable time and resources.
- must have been around the project at least three months more-or-less continuously, preferrably six or more. As mentioned above, use of automated tools to rack up edits like this is a game of Space Invaders doesn't give you the real hands-on, get-dirty experience needed to deal with many of the nuances of Wikipedia's culture.
- while the candidate has little control over this factor, association with/nomination by/opposition by certain users will make me take a closer look, and possibly weigh in on a candidacy I would have ordinarily passed by. This is especially true in close races.