Does a newcomer have the information they need to be a good participant?
Do they know what good participation looks like?
Do they know how to look up and find information they can share with others?
Do they know what’s on the edge of domain of knowledge?
Do they know what the best examples, books, and resources are?
Do they know what tone of voice they should use when they participate?
Do they know they don’t need to be an expert to participate?
Do they know good questions are better than good answers?
Do they know the 20% of topics which account for 80% of discussions?
Do they know who the top people in the field are?
Do they know who’s in charge and who to contact for help?
Do they know you genuinely want them to succeed and will do everything you can to help?
Do they know how long a post should be, to self-disclose information about themselves and reveal their emotional state when they ask a question?
If the answer is no, you have some work to do.