Phillip Lopate believes it should be rooted in doubt:
Ever since Michel de Montaigne, the founder of the modern essay, gave as a motto his befuddled “What do I know?” and put forth a vision of humanity as mentally wavering and inconstant, the essay has become a meadow inviting contradiction, paradox, irresolution and self-doubt. The essay’s job is to track consciousness; if you are fully aware of your mind you will find your thoughts doubling back, registering little peeps of ambivalence or disbelief.
Instead he thinks, “more often than not, the applicant is expected to put forward a confident presentation of self that is more like an advertisement, a smooth civic-minded con job, circumventing the essay’s gift for candid, robust self-doubt.” On a related note, an admissions officer discusses reading essays on the job:
You wouldn’t believe some of the essays kids write. Last year there was an essay about this girl’s sexual exploits, right down to this whole voyeuristic thing about her having sex on golf courses. Why would we want to read about that? We also get a lot of religious-themed essays on why you shouldn’t have sex before marriage. I also got what was basically a report on the negative effects of abortion. People write reports on global warming too. That’s not a personal statement!