The core answer to this question depends on motivation. Motivation comes in the form of intrinsic motivation and extrinsic motivation. Extrinsic motivation comes from outside forces, like a financial incentive. Intrinsic motivation is about internal motivation, such as a sense of satisfaction that comes from doing something, such as sharing information.
Although motivation is at the core of participation in online communities, there are numerous other dimensions to consider that affect what works in one community versus what works in another. For instance, a community devoted to interests (such as hobbies), is different from a community of practice (people who work in the same field such as an acting club or legal or accounting association), which is also different from a community which is mandatory, such as participating in an work-sponsored intranet/social networking platform. Not only are the motivations different in each of these cases, but there are numerous structural differences in the communities. They differ based on the strength of their social ties, size of their groups, group norms. They may differ in the degree of participation, type of participation, technology features, culture of individuals, etc.
Among the many structural elements that are observed in relationship to participation is social embededdness. A 2001 survey [1] found that being connected to a group through recruitment is an important factor in participation. Also, the degree of cultural affinity towards a particular group is important. Considered on a practical level for business, these findings would imply that recruiting individuals to be part of your community and actively engaging them may be critical to its success, and that applies to offline communities as well. Another thing to consider is that growing an online community is likely to be related to how well you can tap into and draw participants from a related community. For instance, an online community about technology standards is more likely to get interest from people who create technology products than from people who sell real estate. Common ideas (know your market) but from a slightly uncommon perspective.
1. Passy and Giugni 2001, Social Networks and Individuals Perceptions: Explaining Differential Participation in Social Movements.
