I always assumed this was a big specification/dev/test fail by Service Now that appeared a while back (London/Madrid/New York days?). Like a lot of the SN documentation there is no advice on how to use it, just a description of what the statuses are. Which is fine except for the traffic lights being completely counterintuitive with what seems to be the most logical interpretation of the achieved/not achieved status.
Like you, our interpretation is:
Achieved = risk has been realised. Not a good thing, and should be red, not green.
Not achieved = risk has not been realised. A good thing, and should be green, not red.
Pending, avoid, mitigate, transfer, accept statuses are all pretty self-explanatory.
I assume they haven't fixed it because people haven't complained, and/or old modules like project management get no love, they work reasonably well (once you work out how you'll apply them with your processes) and SN is too busy working on new stuff to enhance the old stuff. We still use them, generally later in the project once the other statuses become less relevant, but it's annoying, for sure.
