Unfortunately some vendors are more concerned about not admitting mistake. Now, technically if they don't use the admin password they are probably OK. But (A)

Unfortunately some vendors are more concerned about not admitting mistake. Now, technically if they don't use the admin password they are probably OK. But (A) most people don't change their password. Heck, I work in IT Security and I still have admin passwords on some of my devices! (B) It's always good practice to change passwords ... just in case.