The art of practice is a lifelong journey. For the person who aspires to be great, he or she must be willing to practice everyday. They must be willing and have the desire to practice on good days and bad days. It must be a burning desire within. The drive has to be greater than the discomfort you feel from your practice. 

Steven Pressfield puts it so well in his book "Turning Pro"

Once we turn pro, we're like sharks who have tasted blood, or renunciates who have glimpsed the face of God. For us, there is no finish line. No bell ends the bout. Life is the pursuit. Life is the hunt. When our hearts burst...then we'll go out, and no sooner.

I love the line "There is no finish line". There is only one finish line in life and we all know what that finish line is. It is like I tell my gym members, "It does not get any easier, you just get better at it". Keep your practice going everyday.