The maintenance plan for the poka-yoke provides that, if necessary, it is calibrated or
replaced regularly – typically, calibration or replacement is required for PD that suffer
wear and tear which affects their functionality (Score 4)
Even if both calibration and replacement are necessary, the maintenance plan provides
that only one out of the two activities are performed (Score 2)
Even if both calibration and replacement are necessary, the maintenance plan neglects
both activities (Score 0)