A lot of the time, tbh. I've pretty much said this about giving up on a site/forum and even a situation that may occur which I just cannot find it in me to solve.
My motto has always been “if you build it, they will come.”. It takes time, passion and a lot of hardwork to get a forum off the ground. Keep going if you enjoy it and don’t give up unless you don’t have the energy to do it anymore