There are two requirements of an open system.

If you create a great product, communities will inevitably form, with or without your help.

A community needs an identifiable hero and inspiration from within the company.

Most people are oblivious to communities forming around their product.

Companies often feel great if their communities continue to say nice things and buy their products, but if the community says anything negative, the company will retract their community efforts.

Your product should be "customisable," "extensible," and "malleable." Consider Adobe Photoshop. Without the company's plug-in architecture, a community might not have developed quickly.