I advise applicants to address three issues. This advice applies to just about any application, whether hospital CEO or barista.
1) Why you like the job. This may be complex, because it may be why you like the job in that location, why you like that career, why you like the good that evolves from that job. But you need to answer why you like the job. Providing details are important, such as documented history of an interest in the job.
2) Why you are uniquely qualified to do the job. There will probably be more than one person interested in the position and you need to clearly state why your qualifications are superior to others.
3) Why the job will be better if you are holding the position. This overlaps a lot with why you are qualified but there is a difference. You are qualified based on past experiences, the job will be better based on your future performance. You need to not sound arrogant or over-bearing, while still appearing confident.
Good luck with your applications.
Daniel Remick, M.D.
Chair and Professor of Pathology and Laboratory Medicine
Boston University School of Medicine and Boston Medical Center