Why Do Mastermind Groups Take You To A Higher Level

When you were in grade school all the way through your highest level of formal education, why do you think there were tests? Was it really to obtain the highest score so grades would be handed out by scores on tests?
Is it possible that a test date was implemented to create urgency and accountability onto the student so they would formulate the study habits necessary to score well?
Out in the real world, who brings you your accountability?
Mastermind Groups are where like minded individuals meet in person, on the phone or on the internet on a regular basis and share their stories, offer advice from personal experience to each other and create accountability to each other. Are you in a Mastermind Group or have you been in one? Tell us about your experience?