In one installation, we use a hardware NVR, name brand. During a thunderstorm, the NVR failed. Fortunately, I managed to figure out that the 5 volt regulator had failed and patch in an external 5 volt power supply. The camera network was down for 2 days before I could get it and fix it. If we had to order a new NVR, that would probably have added another day. What if your Blue Iris computer failed, do you have a hot spare? Perhaps this wake up call should address all potential points of failure.
Like someone said, Murphy is out there..... waiting.
It is why many of us have SD cards in the cams, and many run a bare bones NVR simply recording.