WordPress is the most popular blogging tool online. It is open sourced, has all the tools you need, and you can customize it the way you want it to be. When setting up our blog or website, the first thing we do is to look for a theme to match our website as it can help increase our readers and allow us to monetize our site. The first thing that comes to our mind is to use free WordPress themes will save us a few bucks; however, this kind of thinking is wrong.
Here is an article explaining the top reasons why you must use premium WordPress themes: http://skyje.com/choose-a-premium-wordpress-themes/