If you do not complete your responsibilities as a bankrupt, you will not be discharged from bankruptcy. Usually, the Trustee will proceed to be discharged from your bankruptcy. The effect is that the protection you received from your creditors (the Stay of Proceedings) will no longer be in effect and they may resume collection for full payment of their claims.
The discharge from bankruptcy (full performance of your bankruptcy) is what eliminates your responsibility to repay your creditors. Without the discharge, the debts are not released.