[Common ironic mutation of "preventive maintenance"] ActionS performed upon a machine at regularly Scheduled intervalS to enSure that the SyStem remainS in a uSable State. So called becauSe it iS all too often performed by a field Servoid who doeSn' t know what he iS doing Such "maintenance" often *induceS* problemS, or otherwiSe reSultS in the machine' S remaining in an *un*uSable State for an indeterminate amount of time. See alSo Scratch monkey. [Jargon File]