Put a new idea out into the world.
Or an old idea, with a new perspective.
Style of writing and visual appeal of a blog are important.
And it's important for money to NOT be the end goal of the blog. All of the successful blogs I've read put information/ideas out into the world for free with no strings attached. They can monetize later, but monetization is not the primary objective for the blogs that "make it".
Like with any business, bloggers identify a need and fill it.
What kind of needs have you identified? How have you tried to start movements? What have you yourself done to be part of that movement? It requires grit, and persevering even when you are the only person furthering your movement.
Say, for example, your movement is environmental preservation. You can sit at your keyboard and type about it all you want, and try to organize everything you want, but if you aren't out every weekend cleaning trash from the side of the road yourself, WHETHER OR NOT anyone is there to do it with you, people will not follow. You need to further your own movement daily, and then let others be inspired by that and join you. If there is nothing to "join" (i.e. a as-of-yet unorganized group of trash-pickers, versus joining you as a devoted trash-picker), then it would be hard to expect people to rally.
With MMM, Pete had a blog, spoke his mind, and did his own thing regardless of whether anyone else cared what he had to say or followed what he did. The results spoke for themselves, and people came on board. And so it went.