Do you mean the Atlassian community, or confluence itself? The Atlassian community is for talking to other Atlassian product users who may or may not be at your organization about how they're using Atlassian products, and troubleshooting together or discussing best practices.
The comments on Confluence are for discussing what's going on with a page. I like to use them to talk to colleagues about a change I'm considering before actually implementing it.
