I believe that the knowledge is power, and being raised in the family of intellectuals, professionals in the humanities and arts (music), I was very curious as a child, and later on I wanted to learn more, expand my skills and knowledge; I felt inclined to the fields that I was interested in. The ICT’s and Internet helped me a lot in synthesizing the creativity and innovation at my work and studies, making them interdisciplinary, so after my Master thesis research I’ve spent lot of time at the conferences, lecturing, working for the industry and education, then I realized that I want to continue with PhD. I like to teach and transfer the knowledge/skills in any form; for specific vocations doctoral work is necessary; it teaches me how to work independently on complex problems, and therefore it gives me better research (is hard!) and analytical skills that I can implement in education and the industry, life and arts as well. It also helps to understand how the mind of fellow researchers works (or should work). There are lots of advantages, and some fun, I believe.
Hope you are happy with my answer.
Update: this is now the official my PhD mission statement.