Here’s my best current understanding of how the eight limbs work…
We have habitual patterns of thoughts (samskaras). These are places the mind tends to go automatically, without awareness. Thinking without thinking.
The goal of yoga is to quiet the mind by becoming passive observers of those thoughts rather than engaging with them / following those patterns.
By becoming detached, self-aware, and fully conscious, we become less reactive and less automatic in the way our mind works. We can remove ourselves from the incessant engagement with thought and instead more fully tune into ourselves — whoever we are beyond our thought patterns.
This begins as a conscious process, but as we practice we will lose our conscious sense of the self and experience a merging between the self and what we are doing (or the self and the collective consciousness / the Universe).
This can also happen in a flow state: we get distracted from activities by taking ourselves out of the activity and into our heads, but the better we are at tuning out distractions and the more we are immersed in the activity (and not ourselves/our thoughts) the better we end up doing at the activity.