Each Health Score model you create will most likely have different components with different associated weightings. For this reason, the thresholds to indicate what a positive and negative score are will differ from score to score you you have the capability to set those thresholds manually here.
First Navigate to the Health Scoring section i.e. Settings > Account Settings > health Scoring.
Open/Click on the Health Score you would like to work with.
On the left-hand side, click on Good / Bad Thresholds.
Input the upper and lower thresholds and click Submit.
You will now be able to identify positive and negative health scores both in a static (color-coded) score and displayed on health scoring graphs/widgets on Dashboards [Below]