Handing a project back to the client, cleanly
Not every client stays on retainer. When a build wraps and the client wants to own their hosting outright, the isolation between accounts on an agency plan makes that straightforward — each site is a self-contained cPanel account with its own files, database and mail, so it can be handed off or pointed at a new destination without any other client on your roster noticing.
That same isolation works the other way too: a problem on one client's site — a bad plugin update, a compromised contact form — never touches the account next to it. Your roster grows or shrinks one clean account at a time, not one shared filesystem everyone has to tiptoe around.
