Loose or Thick Clothing. If the probes lodge in clothing and are too far away from the subject, ECD effectiveness is reduced or prevented.
Miss or Single Probe Hit. The current must pass between the probes. If one probe misses, a second cartridge may be deployed if practical and legally justifiable. Using the X26 ECD in the drive-stun mode as described below may also complete the circuit between the single probe and the ECD electrode.
Low Nerve or Muscle Mass. If the probes impact in an area where there is very little muscle mass (e.g., the side of the rib cage), the effectiveness can be significantly diminished.
Limited Probe Spread. Small probe spreads (including drive-stun) result in little or no effect from NMI and become primarily a pain compliance option.
Wires Break. If a wire breaks (e.g., during a struggle), the current will not flow to the probes. Drive-stun is still available.