Encouraging organizational User-Generated-Content (UGC) creation

We're a big organizatoin, and understand that we cannot support each small unit's learning need, ad that lots of required solutions - can be created by content expert in the organization, without our end-to-end involvement. And see our contribution and support in enabelment. So we wish to encourage User-Generated-Content (UGC) creation internally.

Looking for examples and case studies of successful UGC creation and encouragement in organizations.

and also would love to hear from your experience, what works best:

1. Which basis, templates, explanations to offer in order to encourage content experts to create their own learning nuggets\content.
2. How to get to them with the encouraging and supporting content we will create.
3. What makes people create learning content for other to use (YouTube is packed with such content)? How can we organizationally encourage these qualities?