Veeam Backup for Microsoft 365 backs up data from your Microsoft 365 organization, including Microsoft Exchange, Microsoft SharePoint, Microsoft OneDrive for Business, Microsoft Teams, and Microsoft Exchange on-premises and on-site. Certainly, a comprehensive solution for backing up and restoring

So, Technically Microsoft Office 365 uses SharePoint Online and retention policies to back up data to some extent. However, your responsibility is to manage your data and information as a company. Therefore, you should always have a third-party backup. 

 Veeam Backup for Microsoft Office 365 risks losing access and control over your Office 365 data, including Exchange Online, SharePoint Online, OneDrive for Business, and Microsoft Teams. So, data is always protected and accessible.

 A backup makes restoring your data to your pre-attack instance easy regulatory and compliance requirements: Microsoft 365 has built-in eDiscovery capabilities. However, third-party backup solutions require special tools to easily search within backups and quickly restore data to meet regulatory compliance requirements. 

Veeam Agent for Microsoft Windows allows you to back up your data to Microsoft OneDrive. So, This feature is intended for home PC, workstation, and laptop users who want to keep backups offsite without setting up a backup infrastructure.

Certainly, Cloud-to-cloud storage is a feature that fully protects Office 365 data outside the Microsoft public cloud. Cloud-to-cloud is considered a more advanced backup method for Office 365. That allows you to separate operational and backup data and store them in different cloud environments.