A power-off is a simple fault, with fairly well-defined effects. It's actually one of the easiest cases for a data-storage system to deal with. "Hardware fail

A power-off is a simple fault, with fairly well-defined effects. It's actually one of the easiest cases for a data-storage system to deal with. "Hardware failure" includes all manner of crazy Byzantine faults, many of which are literally impossible to deal with. What this is saying is that TFS's model of the underlying hardware is that it will either execute all writes correctly or stop executing any. Sadly, a lot of hardware has much more complicated behavior than that. A lot of RAID cards in particular will lie about what was actually written, so in a power-off scenario later writes might have made it while earlier ones didn't, writes can be incomplete, etc. I don't mean this as a knock against TFS. It's more of a suggestion that the fault model be expanded to include at least a few more possibilities.