I've been going to discussion boards for years now and I own a couple. What I find is that sometimes a handful of regulars will try to intimidate new-comers to the board, to let them know who's boss around here.
I've even seen where board regulars will only talk to each other and will ignore new-comers, unless of course the new-comer pays the proper respect to the "old guys". Discussion boards cannot grow with just the regulars. If you do not have new people coming to your board it will dry up and die. Kind of like the contracting business. If you rely too much on your previous customers for work instead of trying to harvest new customers your business will die.
I've even seen where two or three guys will attempt to hijack a discussion board. They start out rather decent but as their popularity grows they slowly become self-promoted moderators. They begin saying that this person or that one should be kicked off or this post/thread or that one should be closed or removed. This isn't for them to say but they try to take on that authority none the less.
I participate in an Air Force forum and I noticed that some of this was going on, so I made a post about Trolls vs. Bullies and it must have been an eye opener, because these guys all of a sudden started getting weeded out. That particular board was slow to start moderating and these guys came in under the radar and started chasing members away. This was a paid site so it affected the site owner's pocket book in a very direct way.
This site relies on advertisers and Google ads to make money, but you still need people participating to attract these advertisers and to have folks to click on the ads.
I'm not suggesting that any of these things are going on at this site, but... it still pays to keep one eye open.