The first fallacy of creating a community is just this. The mindset of a hoarder. Gathering anything without a purpose places the cart in front of the horse – or, the business model in front of the raw material. People are the raw material in a Community. Just as a steel manufacturing business does not hoard up strawberries, a Community must eschew the lure of mindless “customer” acquisition at the cost of defining upfront who are being served and with what purpose
Hoarding impacts your community in two equally destructive ways. One, once the purpose of the community is established (post membership acquisition) members discover they do not have intersecting interests or expectations with the rest of the gang. There is no tribe to speak of. They quit. Secondly, a few acquired members are perhaps of the correct profile who would quickly discover there are a sprinkling of non-conforming audience engaged in community activity and will quickly disappear
What about multi-interest communities then? Yes, they do exist. If that is what you have in mind then it is better to think in terms of platforms. A Platform with different communities as tenants. It is perfectly possible – and correct – to design a handful of services as horizontals that each tenant feeds off. Then get onto community (tenant) specific services.
Irrespective of tenancy plurality, member acquisition should not broadbrush to pixalate the specific community picture. The rule of member acquisition remains unchanged