Accountability is best built over time and as a natural outgrowth of relationship. Accountability requires you to take risks at being transparent. Accountability comes out of depth of relationship. You can't stay on the surface and expect to experience the benefits. Be willing to spend time with one another.
Accountability requires that people communicate with one another and that translates into time.
Accountability is a learning process. Defensiveness and pride breaks it down. Be open to learn more about being accountable.