Katara, White Lotus Leader and others in “Unfinished Business”

She's strong.

She lacks restraint.

Korra

Woo-hoo! Hey, why all the doom and gloom, people? We should be celebrating! Three elements down, one to go!

You're getting ahead of yourself as usual, Korra. We haven't decided if you passed your Firebending test yet.

And ever since you were a little girl, you've excelled at the physical side of bending and completely ignored the spiritual side. The Avatar must master both.

Korra

I... haven't ignored it, it just doesn't come as easy to me. But that's why I should start training with Master Tenzin immediately. He's Mr. Spiritual!