You want your maintenance team to maintain more, repair less. Each incidence of unplanned equipment repair, typically the result of a surprise failure, is evidence of a maintenance failure. So the higher your ratio of maintenance to repair, the more successful you are.
Some repairs are part of the maintenance process. For example, the mechanics replace worn, but still serviceable, seals before the seals leak. They may do this on a schedule (X hours of operation) or based upon some condition metric evaluated during regular predictive maintenance.
An electrical equivalent would be repairing a bolted connection, based on the fact that during the predictive maintenance it appeared hot during an infra-red scan and an AC resistance test confirmed it needed repair.
What you don’t want is for the mechanics to have to take a production line down because a seal suddenly started gushing all over the place. In the case of that connection, there may not be time to take production down before the connection fails and you get an arc fault.
