In reference to an article I read a couple of days ago (great post Michele!), many students train while trying to be "like" someone, usually their instructor, but also the list may include their parents, a celebrity (I get the "I want to be like Bruce Lee" deal all the time), a senior student, etc. etc. While this runs rampant in children, this is more common with adults than people may think. It can be anything from "I want my horse stance to look like his horse stance," or "My side kick doesn't look like his. What's wrong with mine?"
While there is nothing wrong with having a model to look after, or an idea of what you'd like to be, the most important thing to remember that you are you, and not someone else. Even if, for example, two people perform the same kata, person A's kata should be different in some way from person B's. Even though they have the same basic movements and techniques, each person's individuality should shine through somehow, and this can depend on many factors: each person's different interpretation of the kata, their personality types, their current moods and/or mindsets, their physical makeup (a 6'5" 230 lb. person's movement certainly would be different from one that's 5'4" 120 lb.).
Each of us have been given special talents, abilities and insights that makes us all unique individuals, and it would be a waste not to let those shine.
P.S. Of course, this applies to just about everything else in life outside of martial arts, right? :)