People want to fit in with the group.  

• Each job has purpose  
• That purpose is of some value to the team 
• People want to be valuable 

How to promote team based roles 

• Use team meetings to clarify individual roles 
• Constantly reinforce each responsibility (big and small)
• Explain the value of each role in different settings 
• Make sure people know each other's role 
• Promote mutual accountability