Organizations periodically review expired content and approve it’s disposition. There are several reasons why reviewing content to decide whether it can be safely deleted (disposed) is important. For example you may need to:
The tremendous momentum we have seen in adoption of Office 365 is driving significant growth in the data enterprises are governing using our Data Governance feature set. To provide organizations with even more granual control in the disposition of unecessary data, today we are announcing the general availability of Disposition Review in Office 365 Advanced Data Governance.
More detail about our new Disposition Review capability can be found here.
Source : techcommunity.microsoft.com
www.office.com/setup : Blogs