Absent a propeller strike, a teardown inspection is almost never indicated between overhauls. Yes, the airframe and engine get inspected annually, but the engine is not "torn down" during those inspections.
The teardown and inspection of an electric motor is trivial compared to that of an internal combustion engine. Generally speaking, you'd undo a few fasteners, pop off a cover, and check/clean the rotor/windings. 15 minutes tops - heck, you could do it before every flight and it'd still be cheaper than paying for the 100-hour maintenance on a GA plane.
