Final answer:
The examiner asks the patient to try a second time in the strength test to assess muscle function accurately.
Step-by-step explanation:
The examiner asks the patient to try a second time in the strength test because it allows for a more accurate assessment of muscle function. By trying a second time, the examiner can determine if the patient is able to generate and sustain muscle contraction, which is essential for normal control of facial expressions. This information is important for diagnosing and evaluating facial palsy and paralysis.