Final answer:
Option 3 is incorrect because psychological assessments are not always completely objective or error-free, as they can be influenced by subjective interpretations and the individual being assessed.
Step-by-step explanation:
The statement that is NOT true concerning the assessment of psychological disorders is Option 3: Assessment is always a completely objective and error-free process. Assessment, indeed, aims to gather information about an individual's psychological well-being and often uses methods like standardized tests and clinical interviews. Projective tests, like the Rorschach Inkblot Test, delve into unconscious processes and are less prone to intentional distortion by the individual. Surveys can also be used to collect data from a large number of people. It's important to recognize that cultural influences and various approaches to personality can affect the diagnosis and classification of psychological disorders. The DSM is a key resource in diagnosing mental disorders but is subject to continuous updates that reflect current understanding and practices in the field of psychology. Lastly, while self-report inventories provide a quantitative measure of personality characteristics, they, along with other assessment techniques, are not infallible and can reflect subjectivity and potential errors.