Yep, a friend of mine was doing a pre-flight, his student was impatient and said, you just landed not 10 minutes ago! Why are you wasting your time? He wiggled the elevator and said 'Hmmmm, that doesn't feel right, hand me that wrench.'
Popped off an access panel, pointed inside and said 'That's why!' The control cable had been frayed down to a single strand.
I trust his student took the lesson to heart...