Though most of the DBSaaS vendors promote the notion their databases are fully managed and doesn’t require anyone to maintain. This is not true. Whether you are running a database on-prem or cloud you still need to run periodic maintenance, monitor the performance, and take care of database security. In some cases, you may still to need make sure the backup and recovery is happening periodically so that you don’t get surprised when the whole machine is lost.
In our experience only few tasks are done by the vendor such as the upgrade to the latest patch/version, system level backup and basic configuration. Some database auto provisioning is already done in the background you don’t have to do them manually. Rest you may need the experts like us to take care so that performance is predictable and proactively managed.