My cousin gave me pause today when he asked me to edit the writing sample he's sending to a prospective employer.
I know, of course, that job applicants -- the good ones -- get their materials edited by other people all the time. It's part of showing due diligence in making sure you don't have typos, etc. But somehow writing samples feel different, and as a manager, I felt obligated to say: No! Do not do this. Your writing sample should reflect your writing, not writing that has been edited by others. Otherwise a hiring manager can't make a good decision about whether your writing is the right fit for the job (and ultimately, even though you want to get the job, it's more important to get a job that you're the right fit for).
But as his cousin, I want him to get the job. So ultimately I said the above to him, and then sent him my edits.