What is the running back’s job?
Most people would give a very simple answer: make plays.
But what exactly does it mean to “make plays?”
To me, a running back “makes a play” when he creates yardage that isn’t handed to him. Make a man miss. Use your breakaway speed to blow by defenders. Drag a defender down the field. Run someone over. Be patient and allow holes to develop.
When a running back successfully does one of these things, it means he has “made” a play. He created yards that weren’t previously available before his actions.