Hard work = tough surrender

"The harder you work, the tougher it will be to surrender"

Great quote from legendary football coach Vince Lombardi.  Simple and effective.  The more invested a player is through conditioning, practice, team building, skill development, film study, etc., the harder it will be for the player to be willing to quit at tough points throughout a game and the season. 

Are your players invested enough to not quit on themselves and their teammates?