Destructive Edit

From MusicBrainz Wiki

The term "destructive edit" refers to an edit that cannot easily be undone/reverted and that involves loss of (possibly good) data.

Edits that are considered "destructive" are never auto-edits; they always go into the voting queue so that they can get extra scrutiny.

While merges and deletions are both destructive, merges are considered less destructive. The general rule is Merge Rather Than Delete, because merges redirect MBIDs rather than destroy them.