Stable. Can drive a wide range of frictional and inertial loads.
Needs no feedback. The motor is also the position transducer.
Inexpensive relative to other motion control systems.
Standardized frame size and performance.
Plug and play. Easy to setup and use.
Safe. If anything breaks, the motor stops.
Long life. Bearings are the only wear-out mechanism.
Excellent low speed torque. Can drive many loads without gearing.
Excellent repeatability. Returns to the same location accurately.
Overload safe. Motor cannot be damaged by mechanical overload.
Low efficiency. Motor draws substantial power regardless of load.
Torque drops rapidly with speed (torque is the inverse of speed).
Low accuracy. 1:200 at full load, 1:2000 at light loads.
Prone to resonances. Requires microstepping to move smoothly.
No feedback to indicate missed steps.
Low torque to inertia ratio. Cannot accelerate loads very rapidly.
Motor gets very hot in high performance configurations.
Motor will not "pick up" after momentary overload.
Motor is audibly very noisy at moderate to high speeds.
Low output power for size and weight.