Pre Employment Question:

☛ They only measure different attitudes about things from different people. Your attitude about something in general cannot be used to predict how you'll react to different & distinct business situations.
☛ They cannot predict behavior because behavior is context sensitive. People act differently in different environments. If you're in sales, and you're way ahead of your quota, you will almost certainly handle price concession requests differently than if you were way behind quota.
☛ They associate success with specific personality types. In fact, personality requirements are different for different jobs. Rarely do any of the tests customize their recommendations by job type or environment. It's simply "This person may (or may not) succeed." This just doesn't happen in real life.