The statement of intent (or, as it is also called, the statement of purpose or personal statement) is a very important part of your graduate school application.  It not only provides a reason for your desire to pursue graduate education, it serves as a writing sample to the admissions committee.  Most committees look very closely at the writing abilities of prospective students.  A very well written essay can boost your chances at acceptance into a program.  A poorly written essay may have the opposite effect.

The focus of the statment of intent should be the reasons that you are applying for admission to the graduate degree program.  The essay should be well written, which is to say, it should be concise and well organized, free of grammatical, punctuation, and spelling mistakes, and two to three pages long, double-spaced.