10. Use poor spelling or poor grammar _ This one should be pretty obvious. Academics on admissions committees are generally high achievers with high standards who won't disregard even simple typos. If your personal statement is not technically perfect, it can make you seem sloppy, lazy, or inattentive, which are not qualities anyone wants in a future colleague. Remember that the people skimming your essay are seeking a reason to reject your application and make the pile of possible admits smaller. Always get someone with strong writing skills to review your essay.
Focusing on negativity _ People face problems from time to time; however, there are those who have faced graver trials than others. If you are one of those people who's had your fair share of problems, make sure that you adopt a positive attitude despite the challenges, and reflect this attitude in your statement. Wallowing in negativity will give off an unfavorable vibe, and enumerating all the trials you've been through will no longer make your essay an interesting read.