There are a variety of ways in which a blog can have an impact on the lives of others. If you're looking to influence others, a blog might just be for you. This article has great tips about creating successful blogs.
Blogging is about writing. If you don't like to write, you probably won't enjoy blogging. But if you've never tried writing, you may have an as yet undiscovered talent that you would enjoy. So try writing a few practice blog posts. Write about something interesting to you. If you enjoy writing, then blogging may be for you!