I learned that the physical poses, the asana, were only one of the 8 "limbs" of yoga, a multifaceted practice ultimately aimed at spiritual goals; asana were meant to strengthen your body to allow you to sit in meditation for long periods of time without the distraction of pain!
of course, this isn't really discussed much in the American yoga tradition, which treats asana (and to a lesser extent pranayama, the breathing practice) as the entirety of it
but the lessons are there for those who seek them out
I was one such, autistically obsessing over it