Most of the time, WordPress plugin developers will require administrator privilege to your WordPress dashboard to manage their plugin adequately. With this access level, the plugin can be installed, activated, and put in a configuration. Furthermore, you can make required changes to the code. If this involves server-side changes, it requires FTP or SFTP access for uploading files and managing server resources. If accessing the server is a requirement, it is advisable to grant these permissions securely by creating a user account with a strong and unique password, which you revoke as soon as the work is finished to maintain the security of your site.