Initially in my yoga practice, I was very strong driven by the desire to "achieve" poses. As though a pose was something I could conquer and move on to the next thing. After several years of practicing in this way, I came to realize that you never actually "own" a pose. You might be able to do it for years and then something changes in your body or your practice and it no longer belongs to you.
Also, I must say that I find commercialized yoga practice to overly emphasize achievement and posture. I don't think you can separate your bodily practice from your mind/breath/moral practices and have them make the same impact on your life. If yoga is truly going to work for us, we have to be willing to put in work in all the areas or "limbs" of practice.
In other words, there is no instant gratification here. We can work on postures without them being the end goal. There are many lessons to be learned along the way. Patience, detachment and kindness toward your body, to name a few.
SUPTA VIRASANA is one of those poses that requires a whole lot of practice and much cultivation of patience. This is not an instantly gratifying pose. But through our continued effort and the generous use of PROPS and BREATH, it might just be worth the wait.