You only get notified of new posts of members you follow. It’s impractical to go in and follow every member, which means when they post, the administrator, and even other members, aren’t notified there is a new post. There needs to be notification set on otherwise it’s really hard to create community engagement. There could be an opt out option in the notifications if members don’t want notifications. Notifications like these are a feature of fb groups and make a huge difference when running community events and experiences where timely interactions create engagement.