The site settings beginning with "topic views heat" and "topic post like
heat" are set to defaults when installing Discourse, but there has not
been a process or guidance for updating these values based on
community activity.
This feature will update them once a month. The low, medium, and
high settings will be based on the minimums of the 45th, 25th, and
10th percentile topics respectively, so that 45% of topics will have
some "heat".
Disable automatic changes with the automatic_topic_heat_values setting.