This is one of the most common misunderstandings in the Microsoft 365 world: the assumption that because your data is "in the cloud," it's backed up.
Microsoft does an excellent job of protecting your data against things on their end — hardware failures, datacenter outages, regional disruptions. Your email and files are replicated, redundant, and highly available. That's real and it matters.
But it doesn't protect you against the things that actually cause data loss for small businesses.
What Microsoft 365 retention actually does
Microsoft 365 includes retention policies and a recycle bin, which are useful. Deleted emails and files sit in a recoverable state for a period of time — typically 30 to 93 days depending on your license tier and settings.
After that window closes, the data is gone. Microsoft's infrastructure is working exactly as designed.
What it doesn't protect against
Accidental deletion. Someone deletes a project folder they shouldn't have. If it's caught within the retention window, fine. If it's not caught for three months, you're in trouble.
Ransomware. Ransomware increasingly targets cloud storage specifically because it syncs so efficiently. If your OneDrive syncs an encrypted file library to Microsoft's servers, that encrypted version is what gets retained.
Employee departure. When an employee account is deprovisioned, the process matters. If it's done carelessly, data associated with that account can be lost before anyone realizes what was in it.
Malicious deletion. A departing employee — or an attacker with compromised credentials — who systematically deletes files can cause significant damage within the retention window.
What a proper backup looks like
A proper Microsoft 365 backup solution takes independent, point-in-time snapshots of your Exchange, SharePoint, OneDrive, and Teams data — stored separately from Microsoft's infrastructure — so you have recovery options outside their retention window and outside their control.
This isn't an edge case product. It's a standard part of a well-managed Microsoft 365 environment, and most organizations don't have it configured correctly or at all.
If you're not sure what your current backup situation looks like, it's worth finding out before you need it.