`findmnt` only reads the mount table, but the task declared `changed_when` on a successful return code and therefore reported a change on every single run. Any btrfs backed user made the whole play non idempotent, which an idempotence check would flag as soon as one exists. The `failed_when` on a non zero return code is dropped along with it, since that is exactly what the command module does by default. Co-authored-by: Copilot <copilot@github.com>