Intelligent file management
OneDrive should continuously monitor files to identify duplicate files and files that have not been used for a certain time. Duplicate files take more space in the cloud and on our local machines when we keep them synchronized, and more space taken means less space available and eventually leads to the addition of extra storage (both in data centers and locally), which leads to more energy wasted, etc. Files that we have not used in a while could be candidate to be kept in the cloud only. Why perform this manually when OneDrive could give us a nice monthly report that would allow us to take action on duplicates and unused files. Duplicate files is a win-win where both users and Microsoft is benefiting, and unused files is a direct win for users and an indirect win for Microsoft as it is a feature competitors don't offer.