Distance badges - fastest run

I apologise in advance for opening a new discussion on a topic that might have been tackled before, but I could only find this discussion (and nothing conclusive). I like very much the system that labels my runs and activities, awarding little badges and medals for the fastest ones: it is a quick tool to see how you're performing and it keeps me motivated. I have understood the marking system - see discussion linked for reference - but I feel like it's contradictory, as the way it labels "short" and "long" runs is a bit arbitrary to me. Or, in this case, it does not seem to be reliable at all. See image attached for reference.
Anybody with a good explanation, or suggestions to fix?
Thank you!
Andrea

Comments
Superusers
I imagine this is not what you were hoping to hear but let me know if this answered your question. If it did, please mark it as a solution so other can look for it if they have the same question.
Superusers
I hope this helped answer your question. If so, please mark it as a solution so others can look for it if they have the same question.