What about beauty beneath the surface?
People may be far more than what they display "objectively".

Song 'Beauty And The Beast' by Celine Dion and Peabo Bryson:
http://www.youtube.com/watch?v=pgYEJHJXFB4

"If you look closely at a tree you'll notice its knots and dead branches, just like our bodies. What we learn is that beauty and inperfection go together wonderfully."
- Matthew Fox

"Love is vulnerability. Happiness is vulnerability. The risk of being vulnerable is the price of opening yourself to beauty and opportunity. Being vulnerable is not about showing the parts of you that are polished; it's about revealing the unpolished parts you would rather keep hidden from the world. It's about looking out into the world with an honest, open heart and saying, 'This is me. Take me or leave me.'"
- Unknown

"A person who only sees with his eyes and not his heart misses the details of beauty."
- Evie Lynn Fritz

From the song 'Don't Need You To Tell Me I'm Pretty' by Samantha Mumba:

I don't need you to,
Tell me I'm pretty to make me feel beautiful.
I don't need you to,
Give me your strength to make me feel I'm strong.
I got all of this strength that I need here
inside my own two hands,
All that I want is your love and respect for who I am.
What I really need,
Comes from deep inside of me.

Don't need you to tell me I'm pretty to make me feel beautiful,
Don't need you to make me strong cause I'm strong all on my own,
Doesn't come from outside,
This beauty I know,
Comes from inside my soul.

https://www.youtube.com/watch?v=OuCIcIQmBgU

A case of a girl projecting confidence naturally? Or maybe other things make up for the lack of confidence?

From 'What Makes You Beautiful' by One Direction:

You're insecure,
Don't know what for,
You're turning heads when you walk through the door,
Don't need make-up,
To cover up,
Being the way that you are is enough,

Everyone else in the room can see it,
Everyone else but you,

Baby you light up my world like nobody else,
The way that you flip your hair gets me overwhelmed,
But when you smile at the ground it ain't hard to tell,
You don't know,
Oh, oh,
You don't know you're beautiful,
If only you saw what I can see,
You'd understand why I want you so desperately,
Right now I'm looking at you and I can't believe,
You don't know,
Oh, oh,
You don't know you're beautiful.

That's what makes you beautiful.

http://youtu.be/QJO3ROT-A4E