I sometimes forget just how difficult it is to get a forum going. Rarely is anyone going to start a thread in an empty forum or even participate in a thread that only one or two people have participated in. Plus, unless you have chosen a tight niche, the chances are that there are more established forums where large numbers of people are talking about the same stuff.
The length of time and the amount of effort that has to be put into getting a forum off the ground can be deceiving, even to those who have gone through it before. Women probably experience something similar in pregnancies, in that they forget how bad it was.
I've started forums late at night, when I had some spare time, thinking that I'd be able to get it going, and there have been times when that just didn't happen. On the other hand, I started a support forum for a particular disorder that my nephew, whom I was raising, had, in late 2000 or early 2001. That forum just took off. My nephew is in his twenties now, working and living several states away from me, yet that forum is still going strong. Although I am still a co-administrator, I gave the administration over to someone else, but I check in with it every now and then. It has become sort of like a grown child. You no longer have to feed and clothe him, or make sure that he gets up for school, but you're still pleased to know that he'd doing well.