Professionalism is, "the competence or skill expected of a professional." "the key to quality and efficiency is professionalism"(GOOGLE)
In order to be a successful Athlete you should value the importance of the game over wanting to just be a winner! The values of any sport is the key to understanding the true lessons that you are being taught!
Sports is becoming only pure entertainment which is why we have more professional Athletes rather than successful Athletes!
Values that Sports teaches you-
4. Ability to work well with others
5. Not to give up when times get tough
8. Leadership skills
9. Communication skills
10. Listening skills
The trend starts at young age when we see professionals compete at the highest level! Our youth is fond of all the stardom and hype behind it... Can't forget all the money they make too! That is all they see. Some of these athletes are bread to be professional Athletes, they leave school early without graduating not realizing it will all come to a end someday.
So many athletes get hurt and have short lived careers. Some never really got the opportunity to make the big buckets. Most of them have nothing to fall back on. So they end up back home getting into trouble, or training kids to be exactly what they use to be or could not be! There is nothing wrong with it if they are also teaching the values of true Professionalism and molding a successful Athlete!
The point I'm making is, Professionalism in a athlete is training to be a Successful Athlete! Here is a great read on Workforce Professionalism