Microsoft 365 holds a 99.9 percent uptime record. It also employs geo-redundancy, where Exchange Online data is continuously replicated to multiple databases in geographically-dispersed Microsoft data centers to provide data restoration in case of large-scale infrastructure failures.

Microsoft 365 also provides a Recycle Bin with which users can restore deleted mailbox items without the need for the admin’s intervention. Even if the Recycle Bin is emptied, administrators can help users restore those items.

Even though Microsoft provides these measures, they're not a valid substitute for backups due to the following reasons:

The Recycle Bin in Exchange Online is limited, as the deleted items are retained in the bin for a maximum of 30 days (120 days max for calendar entries). Once the retention period is up, the items will be permanently deleted and can’t be retrieved.

A backup is a copy of a data you can use to restore historical data. Even though Microsoft has a copy of all your data in multiple locations, it cannot be used to restore particular items like a single email or contact back to your mailbox.

Only a backup and restoration solution can help you overcome all these disadvantages.

What does an Office 365 Mail backup solution protect against?

A potent Office 365 mailbox backup and restoration solution can protect you against the following issues:

Accidental deletions: Accidental deletion of mailbox items can happen at any time, and by the time users notice that an item has been deleted, it may have been purged from the Recycle Bin. With a backup and recovery solution in place, you can restore the deleted item in an instant. Unlike the native Recycle Bin, there’s no limitation on the duration within which you have to perform the restoration.

Intentional deletions: Insider threats are a major risk to any organization, and a rogue employee could easily delete any data on purpose. With a backup and recovery solution in place, you can restore the deleted item in an instant, even if the item has been purged from the Recycle Bin.

Hardware malfunction: Microsoft servers are placed in geographically diverse locations, but it’s always a good practice to have a backup of your data yourself.

Also, to know more about Office 365 Migration or Migrate to Office 365 from Exchange 2013 visit O365CloudExperts.