Thanks for information :+1: Now, it's clear for me :) 

I was also thinking about moving definition of `CLOSED_ACCOUNT_FLAG` to some settings (not necessarily Wikia/config repo but maybe `DefaultSettings.php`) before running the maintenance script so we won't need the `defined( 'CLOSED_ACCOUNT_FLAG' )` check. But maybe it's not a big performance improvement and it's not worth changing now.