I disagree. An analytics tool that's correct 99.9% of the time is not 0.1% less valuable than a tool that is always correct. It's 100% less valuable.

Outage is the easy failure mode. I can work around a service that's up 80% of the time, but is 100% correct. A service that's up 100% of the time but is 80% correct is useless.

Well hang-on, in this case it is _neither_ reliable in terms of availability _nor_ correctness. Worst of all worlds.