No plant runs on a single maintenance strategy, and no plant should. The real question isn’t which of reactive, preventive, or predictive maintenance is “best.” It’s which mix fits which asset, because treating a $4,000 conveyor motor and a $400,000 filling line the same way wastes either money or uptime.
Reactive maintenance: fix it when it breaks
Reactive maintenance means exactly what it sounds like: the asset runs until it fails, then gets repaired. It isn’t automatically the wrong choice. For low-cost, easily replaceable parts where a failure doesn’t cascade into a line-down event, reactive maintenance can be the most efficient use of a maintenance team’s time. The problem is when reactive becomes the default for every asset, including the ones where a failure means hours of downtime and a missed delivery window.
Preventive maintenance: fix it on a schedule
Preventive maintenance moves the work to a calendar: service the gearbox every 90 days, replace the belt every 6 months. It catches a real share of failures before they happen, but a fixed schedule doesn’t know the difference between a line running one shift a day and one running three. An asset can fail well before its next scheduled service, or get serviced too early when nothing was wrong yet.
Predictive, condition-based maintenance: fix it when the signals say to
Predictive maintenance triggers work from the asset’s actual condition, vibration, temperature, cycle counts, downtime patterns, rather than a date. Nulogy Maintenance is built this way: it triggers and prioritizes work orders from real machine signals instead of a fixed calendar, so machine condition, downtime, and work orders live in one connected system rather than three separate tools. A maintenance lead sees the pattern building on a specific asset and opens the work order before the failure, not after.
How to decide which asset gets which strategy
A practical starting point for a plant manager or director of continuous improvement:
- Reactive fits low-cost, easily replaceable, non-bottleneck components.
- Preventive fits assets with well-understood wear patterns and where a scheduled shutdown is cheap.
- Predictive fits your bottleneck assets, the ones where an unplanned stop cascades into missed OEE and delivery commitments.
Most plants find that a small number of assets, often the same ones driving most of their shortstop and downtime minutes, are worth moving to condition-based monitoring first, rather than trying to convert the whole plant at once.
What changes once maintenance and downtime share a system
The real shift isn’t the maintenance strategy itself, it’s whether the team can see the operational metrics that actually matter alongside downtime and OEE in the same place. When a shortstop pattern and a maintenance work order live in separate systems, someone has to manually connect the dots, usually after the third or fourth stoppage. When they live together, Nora can surface the connection directly: Line 5 has had 12 shortstops this week, all on the same conveyor motor, here are the last three work orders on that asset.
A note on cost, not just uptime
The financial case for shifting an asset from reactive to predictive isn’t only about avoiding downtime. Emergency repairs, rush parts shipping, and overtime for an unplanned weekend fix are usually more expensive than the same repair done on a planned basis, once the pattern is visible early enough to schedule it.
Moving even two or three bottleneck assets from reactive to predictive maintenance is usually enough to see a measurable shift in OEE within a quarter. Explore how Smart Factory tracks real-time OEE, see how plants get real-time visibility into what’s happening on the floor, or look at what good production monitoring software looks like for a manufacturing plant to see what the transition actually looks like.
