Seth Godin says it’s never too late to start a blog. On this advice, I’ve started quite a few over the past several years.

Starting a blog is easy. Keeping up with a blog once it’s started is the hard thing. My record is Scarlet Letter Bible. It ran for about 10 months, from July of 2010 to May of 2011. I’ve had a couple others, Caspar World and iCaspar, that I’ve restarted several times each. This blog is on it’s second incarnation.

What makes blogging hard is keeping focus. Scarlet Letter Bible ran well for me because I knew exactly what the blog was about. When I realized it wasn’t my wheelhouse any more, or that I didn’t want to be, I made a conscious decision to stop. In my less successful attempts, lack of focus precipitated failure.

Sitting down to write and having to decide again each time what to write about, and wondering how that connects to what you wrote about yesterday — that’s hard. Too hard for me. Without intending to, and partly because I didn’t know what my intentions were, I stopped writing. Then, months later, I’d realize that the project was left hanging.

Another blogger, Mary Jaksch, says that choosing your topic is one of the most important decisions you make when starting or restarting a blog. While she’s mostly focused on choosing a topic that will rank well in search engines, part of her advice is to choose something you’re passionate about. In my experience, the key to success isn’t just passion but keeping focus. As with any project, sometimes its success depends on your ability to focus for a while on something you’re not particularly passionate about.

It’s important to have a topic you’re passionate about. And, depending on your aims, it may be important that your topic ranks well on Google. All the advice about publication scheduling, guest blogging, social networking probably has some merit. But more essentially, blogging requires focus. You need to know why you’re bothering, otherwise before long you won’t bother.

There’s no garden without a gardener, and there’s no blog without a blogger. And there’s no blogger without focus.

Blogging, as it turns out, is the same as most things worth doing. Find your focus, and whatever else develops, you’ll do alright.