Question and answer sites tend to work best when the people who know the answers see the questions. Having more people from your team active on the site increases its usefulness. The best way to accomplish that is to personally invite others to contribute to the site. But once people are using the site, they might forget to look for questions they are uniquely suited to answer.
What features does Stack Overflow for Teams provide to notify others of things they might find interesting or be able to answer?