Because the "Other Mental Health Discussion" forum is specifically meant for topics that don't fit into another forum, your topic will always be moved out of that forum if you choose to post it there if another forum is a better fit for the topic. This is in order to maintain the focus of that forum and keep it from being overwhelmed with dozens of new threads every day where a member feels it's appropriate to that forum.
We ask that people read the "Read this first" at the top of any forum you visit, as some forums have specific posting guidelines. For instance, in the forum posted, there's this:
https://forums.psychcentral.com/othe...%3D%3D%3D.html
In short, we have multiple forums for a reason, to help keep things organized. If everyone could just post to a single forum, that would quickly get out of hand with the number of posts and would negate the purpose of having multiple forums in the first place.