FOD kills 14 more. (Foreign Object Debris/Damage)
But I thought they usually move the flight controls through their motions and make sure the control surfaces respond.
Yep, FOD in the cockpit. And yes, part of every engine runup on the runway prior to brake release is a controls check — partial left, full left, partial right, full right, full back, full forward, rotate around — check freedom of the controls and proper deflection of the flight surfaces, hydraulic pressure OK, no warning or caution lights.