Blogging can be a powerful way for you to build your personal brand and increase the visibility of your company within your industry. Ideally, both at the same time. Your end goal, of course, is to become a top leading expert on the topics that matter to your niche. And when you're first starting out, committing to a niche is important. You must own and dominate it.
Yet, a day will eventually come when you've exhausted your niche. You'll realize that you have finally worked "until you no longer have to introduce yourself," as the great anonymous once put it so eloquently.