Telling personal stories in your applications materials is a good thing, but choosing the right type of story is important. The applicants in the above examples have done a great job of choosing stories that showcase their growth, dedication and skills.
The first candidate tells a story about family, showing how her upbringing led to dedicated study habits. The second candidate demonstrates how he overcame a fear by traveling and pushing his boundaries. Finally, the third candidate shows long-term commitment and camaraderie by describing his favorite extra-professional hobby.