I teach creative writing girls to some high school girls on the weekends, and I was helping them with their college essays. And a girl remarked that in an interview they asked her why she liked theater, and she was completely unable to articulate her passion. I thought that was the root of why her essay wasn't effective. So we all took some to write about what we love/like. Here's what I wrote:
I like design because it combines art with emotion for an effective purpose. It makes you feel something through well crafted visuals and can make you have an "ah-ha" moment and usually all subconsciously. Design is thoughtful and enticing, always a mystery of details--why is that there in that way in that color in that font in that medium? Why do I want to look at it and touch it and interact with it? Design is the tangible creation of my curiosities.
I like this concept and feel like I articulated it well. I found a common theme in being able to speak about your passion: define--and not in a dictionary definition sort of way, and say how it relates to you specifically.
I'm curious what your interests are and how you would answer, "Why do you like...."