The days when my yoga practice was achievement-based are long gone. I'm all for setting goals and intentions, but yoga poses are no longer my desired outcome. Sure, I think it's super fun to attempt challenging arm balances and inversions, but I am almost completely detached from the outcome of individual practice sessions.
Instead, I look to my yoga practice on the mat as training for life off the mat. This work will be my work for my entire life. The overall arc and process of yoga is that of moving from EXTERNAL engagement to INTERNAL experience. My mat practice is simply the set-up to sit comfortably in long-held meditation, it's the training-ground for quieting my mind.
Nicholai Bachman refers to this process as "yoga as NIRODHA." In other words, yoga is the process of calming down the heart-mind. Part of this work might be facing vigorous asana practice with a calm, quiet center. And part of it might be accepting my limitations on the mat, just as I hope to do in my day-to-day life.