Good tips, but I'd add one more requirement: the group who are interested in what you're writing about should be a group with money to spend. Advertisers gener

Good tips, but I'd add one more requirement: the group who are interested in what you're writing about should be a group with money to spend. Advertisers generally have a lot less interest placing ads with audiences who will never pay them. There are certain niches where you can passionately write about stuff, amass a large audience, and discover that audience is very poorly monetisable. Best to avoid that if you're looking for income.