Together with the job description, a candidate's profile is designed to indicate what a candidate should be like. An idealisation, it sums up the qualifications of the ideal candidate and as such deters unfit applicants.
An illustration of this, Unicef wants its campaign director to be a philanthropist with a heart for the third world, a masters degree and at least 7 years of relevant experience. He or she should also be a visionary leader, a manager, a superior communicator, a team-builder, a computer wiz and a financial expert.
Very few people could ever fit that description completely, but nobody has to. The idea is that people, who are genuinely interested in the job and largely fit the description, will reply. A good job hunter can read between the lines and is able to identify the key words of a message. He or she knows that it is more important to answer to the gist of the message than to each and every individual aspect of it.
Somebody who wants a job and who is not genuinely interested in Unicef will not bother applying here. People with a keen interest in developing countries and a passion for an international career, will apply. Motivation still is a key element when it comes to finding the right job.