Businesses classify customer attrition as active/passive and voluntary/involuntary. Active attrition is when customers actively leave due to dissatisfaction with the product or service. If a customer gradually becomes less engaged over time and leaves without communication, it's passive attrition. Voluntary attrition occurs when customers decide to terminate their relationship with a company on their own terms for reasons such as pricing or dissatisfaction. Involuntary attrition happens when customers cannot keep using the product or service due to external factors, such as a failed card payment or billing mishap.