What matters most to you when creating a new forum? I find both can work hand in hand but many people like to start new forums for just making money and in the end it never works out for them. I think people should concentrate on creating a stable community before even thinking about generating revenue from it and money will come in time.
I never start a community for the purpose of money. At first it takes hard work and dedication, and then you can think about money after your forum is stable and well developed.
Running a community is WORK. Work takes time and time is money. As a full time web design freelancer I came to appreciate the value of TIME. So now I don't do anything without thinking about money too. All the effort into running a community is better when you're getting some in return. An admin who's working for free will lose interest. An admin who makes a profit from a community will want to work even more, will PAY for more features, making it even better so everyone will benefit in the end.