Costs

In the case of a departed user on OneDrive, there may be a cost associated with data from now-unlicensed accounts remaining in your tenant. Many people might not like hearing that, and it does seem a little petty of Microsoft to count it differently from the overall amount of storage you are allocated. On the other hand, for the Information Governance part of my day job, it’s not the worst thing to have a mechanism that forces you to consider why that data is being retained and what decisions were made about it.