Final answer:
William Glasser did not assert that all mental illness is simply irresponsible behavior; rather, he believed that ineffective behaviors in meeting needs, often due to a lack of meaningful relationships, could lead to issues classified as mental illness.
Step-by-step explanation:
Glasser's view on mental illness can be understood as partially true. He believed that mental health issues might arise when individuals fail to learn effective behaviors to satisfy their needs, often due to a lack of meaningful relationships. These behaviors can lead to what is perceived as irresponsibility. Glasser's theory suggests that the struggle to meet basic needs can sometimes manifest as what we categorize as mental illness. Therefore, while Glasser's emphasis is on responsibility and relationships, it is an oversimplification to say that all mental illness is merely irresponsible behavior. The statement that Glasser believed 'individuals labeled as mentally ill are exhibiting irresponsibility behaviors' does not fully capture the complexity of his views or the multifactorial nature of mental health disorders.