The Case for Office365 Backup
Microsoft takes care of quite a bit, and provides a great service for their customers. However, Microsoft's primary focus is on managing your Office 365 infrastructure and maintaining uptime to your users. They are empowering YOU with the responsibility of your data.
The misconception that Microsoft fully backs up your data on your behalf is quite common, and without a shift in mindset, could have damaging repercussions when this responsibility is left unattended.