Tom LaRock shows us that we can pause the SQL Server service, as well as what that gets us:
By pausing the SQL Server service before restarting the instance we allow end users to continue their work uninterrupted and we also stop any new connections to the instance. This is a nicer way of telling people to “get out” of the database in order for the server to be rebooted. I wouldn’t leave the server paused for 60 minutes of course, but I would rather use this method than forcibly disconnect users and rollback their transactions.
This is a nice way of bleeding the service dry before taking an instance down for maintenance.