Why Do Girls Dress Like This?

I asked this question earlier but id like to get more answers lol. No disrespect but i saw one of my friends wearing an outfit that was slightly more revealing than other clothes she wore. You could easily see her and i felt a little uneasy because i accidentally looked at her chest since her ensemble was so scantily clad. Did she want to be noticed? Do most girls dress like that so guys can look at them? Do you like to dress like that?