On motion of the defendant, the court shall dismiss the action in whole or in part, as justice requires, if: (1) Upon sustaining a preliminary objection to the plaintiff’s complaint, the court determines that a dismissal is required; (2) The plaintiff has unjustifiably failed to exercise reasonable diligence in prosecuting the action; (3) The plaintiff has failed to pay the full amount required by the judgment within time allowed. (Acts 1985, No. 85-548, p. 802, §1301.)