When a credit card holder has paid off all their outstanding balances and has not made any new purchases during the billing cycle, their bill will reflect a zero balance. This indicates that the cardholder has successfully managed their credit and has not accrued any additional debt. It is important for individuals to consistently review their credit card statements to ensure they are staying within their means and maintaining a healthy financial standing. By diligently managing credit card usage, individuals can avoid accumulating unnecessary debt and maintain a positive credit score.