The Community user deleted my question! What gives?

The Community user will automatically delete old abandoned/dead questions in the following circumstances:

If the question is more than 30 days old, and ...

  • has −1 or lower score
  • has no answers
  • is not locked

... or ...

  • it was closed and migrated to a different site

...or...

  • it was migrated from a different site, and then rejected

... it will be automatically deleted. These are termed "dead" questions (RemoveDeadQuestions, RemoveMigrationStubs in the case of a migration or RemoveRejectedMigrations in the case of a rejected migration).

If the question is more than 365 days old, and ...

  • has a score of 0 or less, or a score of 1 and a deleted owner
  • has no answers
  • is not locked
  • has view count <=the age of the question in days times 1.5
  • has 1 or 0 comments
  • isn't on a meta site

... it will be automatically deleted. These are termed "abandoned" questions (RemoveAbandonedQuestions).

These checks are run every week across all sites.

If the question was closed more than 9 days ago, and ...

  • not closed as a duplicate
  • has a score of 0 or less
  • is not locked
  • has no answers with a score > 0
  • has no accepted answer
  • has no pending reopen votes
  • has not been edited in the past 9 days

... it will be automatically deleted. These are "abandoned closed", and are termed as RemoveAbandonedClosed.

This check is run every day across all sites.

See also: The official "How does deleting work? What can cause a post to be deleted, and what does that actually mean?" FAQ meta post.