The only thing, inside the torque convertor that would cause a compete, drive failure, would be a turbine hub failure. That is what the input shaft connects to, inside the converter. Input shaft could also be broken.
As RJP says, the stator will cause a loss of take off power, it only works when there is a differential in motion, between the output and the engine speeds. The oil spirals, inside the converter and is redirected, threw the stator and back against the pump side (outer converter housing), to increase the engine torque. When the turbine starts moving, it starts loosing it's torque multiplication. When the sprag clutch fails, it can't redirect the fluid, it just spins.
90% of the time, that a convertor fails, it will cause the trans fluid, to become contaminated with with metal, sticking spool valve and pressure relief valves. It makes a BIG mess of any close fitting parts.
Added:
Front pump failure would also cause a "no drive" condition. Both would cause a vibration.