The sole aim of Yoga is self-awareness.
Does this seem shocking? Isn't Yoga a physical exercise practice?
No, it's not an exercise practice, at least not the Yoga that has existed for millennia. The true goal of Yoga is to become aware of oneself on all levels of one's being.
Humans are not simply physical.
Besides our physical body, we also have a prana (energy) body, a mental body, and even more subtle levels of being. But most of us only know ourselves as physical beings. We're missing out by not knowing the true extent of ourselves.
Yoga is a means to discover and experience, to "realize," all the levels of ourselves.
Once we attain complete self-awareness, we also obtain mastery of ourselves.