Webmasters believe that a lot of money can be made off of discussion forums for several reasons. The main reason people see a lot of money in them is because they have an enormous amount of page views and return visitors. It is very difficult for a normal website to get those two things and very easy for discussion forums to get them. People focus on that and rush to start up a discussion forum only to give up and let it die after a short period of time. The reason is because many people do not take into consideration how important actual signups are. A lot of people will go to a forum everyday and read through things but never sign up. If people do not sign up the forums are worthless.

Something that can be done to entice people to sign up are offer rewards for those that sign up. You can also have a posting contest by giving away something to the first person to reach a certain number of posts. Another thing is to start a controversial thread that will force people to sign up and participate in the discussions. No matter what you decide to do to get people to sign up try and make sure that it is planned out before starting the forum. If you think about that after the forums have been started it may be too late.