I have some good news. There has been an issue going on for a while now where the Ideas automation system was misbehaving and setting some Ideas to "Not Planned" prematurely. I finally got this corrected this week. As a result, you will likely see all Ideas created since July set as New as they weren't recognized by the automation tool previously.
I'd also like to announce some changes to the thresholds themselves. Previously Ideas that were at least 180 days old and in the bottom 50% were automatically set to "Not Planned" I have significantly reduced this to the bottom 10%. I think we can all agree if an Idea can't climb out of the bottom 10% after 6 months, it is not a high priority. I think this will reduce the number of times people feel an Idea is archived too soon.
Lastly, all delivered Ideas will now always remain view able so we are not hiding our accomplishments.
I hope these changes make for a better Ideas automation experience.