Office 365 makes it easy to lose valuable data regularly, unpredictably, unintentionally, and for good For all the convenience, reliability, productivity and economy it delivers to your daily workflows, Office 365’s extremely limited versioning, retention and retrieval capabilities make it nothing less than a ticking time-bomb for your organisation.
When hit by the need to restore backed-up data to safeguard the continuity of operations, with Office 365 you’re up against a number of issues, from insufficient retention (14 days by default), to clumsy and expensive storage extension. The responsibility for putting backup in place is yours.
Remember: Microsoft DO NOT backup your Office 365 data.