Answered by Jill Stanton, Entrepreneur & blogger
I think Slack communities can be amazing for paid offers because people are incentivized to use them (before they paid for it)! For free communities though, I personally find that Facebook Groups tend to be "easier" to use for people as they are crazy familiar with FB and typically check it every day.
Slack (or free forums for that matter) can be seen as "another platform" they have to remember to check and use.
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