Quote from a piece of work which is quite old (from 2004 I think) but still a very good read
if you're thinking about applying to b-school:Getting into a top 5 MBA program
"...admissions consultants are invariably not the kind of people that a candidate to a top school wants advice from. Most did not ever attend a top business school themselves, and those few that did were essentially not successful enough to find reasonable jobs afterwards – and thus got into the essay editing business. We encourage you to get someone else to look at your essays and make suggestions, but pick someone who isn’t being paid on the basis of how much of your time they take, or how many changes they suggest you make. Perhaps there’s nothing wrong with your essays at all!"
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