@BCS
Some reasons why someone would change how they look:
[ol]
1. Above all else, wanting to look nice
2. Personal expression and wanting to distinguish yourself (particularly pertinent considering she's wearing a uniform, and couldn't change on short notice)
3. Wanting to show of youth
4. Following fashion trends
[/ol]
And a myriad of other possible reasons. If you genuinly think that wearing a shorter skirt makes you look like a whore, then go ahead. Just know that 99% of women would disagree with you