Philip apparently became frustrated with Blogger's limitations. He writes:
I’ve always been hesitant to move this blog over to WordPress since I knew it would be a lot of work, and I liked that Blogger (Google’s blogging platform that I started with) was a very easy and inexpensive way to keep the blog running.
However, as time went on I felt stronger and stronger that the site needed a redesign, and I never felt the Blogger platform allowed me enough flexibility to do what I wanted.
You can read Philip's article at http://bloodandfrogs.com/2013/10/transitioning-from-blogger-to-WordPress.html.