Jean-Pierre, This is a natural follow on realisation, yes there are advantages in classifying maintenance task in a CMMS using this breakdown for the following reasons:

1. Different task types have different scheduling rules and pre-requisites

2. As you suggest the KPIs for each task type may be different.

Splitting immediate and deferred corrective maintenance implies that there is urgency with immediate corrective, that no pre planning or preparation is possible, and that the impact of failure is high (SHEL, loss of production or product quality). where as deferred corrective maintenance suggests you can live with the impact of failure, and it is lower. This means you are already categorising the importance and criticality of the equipment and corrective maintenance you do on it. IN KPI terms you would seek to reduce and eliminate as much immediate corrective maintenance as possible. Another contributing reason why immediate corrective maintenance for higher impact failure modes may be necessary is because of detectability. If the failure mode is not noticed and is sudden with no discernable symptoms of failure that may make it amenable to on-condition, then you have a harder job or ameliorating the failure mode. It may be necessary to apply the RCA process as a priority to look for preventable rot causes.

I will put KPIs and how they relate to this taxonomy of maintenance tasks in a later blog. Thank you for your feedback.