FAQ 里写的算是比较清楚了。。差不多也是被玩坏了吧（ unlimited 实际上也是不可能的）
Since starting to roll out unlimited cloud storage to Office 365 consumer subscribers, a small number of users backed up numerous PCs and stored entire movie collections and DVR recordings. In some instances, this exceeded 75 TB per user or 14,000 times the average. Instead of focusing on extreme backup scenarios, we want to remain focused on delivering high-value productivity and collaboration experiences that benefit the majority of OneDrive users.

其实我觉得也蛮无语的，给 office365 用户 10TB 空间多好。。。
至于免费用户的容量，这个怎么调都是无可厚非的，毕竟用户没有给钱……