Differentiate, or die!

Never write something that someone else could write.

Too often, clients in their essays with something like, This will allow me to achieve my long-term goal.

Why do you even assume that the reader remembers your long-term goal? That was pages ago :) Seriously, use every single opportunity to remind busy readers of what you are trying to achieve and why you care about it. 

Like all humans, admissions office readers learn through repetition. Learn how to say the same thing in a different way. Paraphrase your specific goals. Never use a generic phrase like "my short-term goal" or "my long-term goal." Just because that phrase appears in the question you don't need to repeat it in your essay. You have specific goals. Remind them what your specific goals are at every opportunity.