According to the 1% rule, in a typical online community, only 1% of users create new content and account for almost all the action. 9% of users will participate but occasionally contribute, and 90% of users are lurkers- observes, but do no participate.
This participation inequality can be adjusted, using different ways:
Show your community you care. Lurkers need to feel that they can contribute; use surveys, encourage them to comment and share knowledge.
Make your community involved . If the content is relevant and targeted for your audience, engagement level will rise.
Enlarge your community. Bigger community=more users are creators and contributors.