While I was in the army, I learned the essential skills of discipline and self-management.
Motivation is what drives us to try our best, but discipline is what keeps us trying until we are the best. As I progressed through different roles and life experiences, I began to appreciate this skill so much more. Discipline was invaluable in enabling me to set and achieve goals at work, in the gym and even with learning music.
My employer in America had a fleet of Peterbilt trucks that he maintained with great pride, and it was imperative that at the end of every day they were cleaned (as best we could), lined up and left looking professional, despite how tired and over the day everyone felt. At the beginning of the season we found this task very easy to accomplish, because we were all fresh, highly motivated and excited to be driving a fleet of big, powerful American trucks. 6 months and many 18 hour harvest days later, it required much more of a conscious effort. It took discipline to consistently maintain the professional standard even when all I and everyone else wanted to do was get some sleep.