Sign adatabase

What is the meaning of sign a database?? If one notes Id of a developer wants to delete from ACL and from admin side permanantly. then will there be a problem??

Subject: sign adatabase

Signing a database is done from the Administrator client. All databases in production should be signed using a special ID used only for signing databases, so that code execution never depends on any administrator or developer always having access to your servers. If personal IDs are used, personnel leaving the company may cause problems.