[birdyrooster]

Perhaps an "outage" label causes the incident to trigger a more widely attended post-mortem meeting and so they are careful not to over-use it.

[blaser-waffle]

"Incident" could mean several things.

Outages mean down, badly, and require RFOs. In my experience working at an ISP we only did any sort of "blame-game" if customers demanded an RFO. We still did post-mortems but usually in a more gentle, roundtable way.