Lets say you have a Topic Great
Topic: Great has
80% Occurrence (80/100 Reviews)
and 100% Neutral Sentiment
Why does the Topic not display positivity?
This is working as intended because The Explorer is finding the Sentiment on the Topic level. Let me give an example with the review text:
"The rooms are great and the staff are awful."
The Explorer would find Topics such as
-Rooms
-Staff
-Great
-Awful
When the Explorer does sentiment analysis for the Topic: Rooms or Staff the system takes into account certain sentimentally loaded (adjectives describing) terms pointing towards that Topic.
So in this case, Rooms - Positive, and Staff - Negative.
Now when we check the Topic: Great. The system tries to find any sentimental terms pointing towards that Topic: Great. In this case, there are no sentimental terms because the Topic: Great itself is sentimental. Thus, it is labelled Neutral similarly to the Topic: Awful.
Now back to your question above, about the Topic: Great, that is just a lot of terms of positivity that should be labelled neutral because there are no sentimental values pointing towards it.