Key points
- A CMMS is built around the asset register: one permanent record per machine, building system or vehicle.
- Its core modules are work orders, preventive maintenance schedules, fault reporting, inspections and spare parts.
- The value comes from history: once every job is recorded against the asset, downtime and cost per asset become answerable.
- A spreadsheet stops working when more than one person has to update it, or when schedules depend on meter readings.
What a CMMS actually does
Strip away the vendor language and a CMMS does five things. Each one replaces something a maintenance team usually does on paper, in a spreadsheet or in a group chat.
| Function | What it replaces | Question it answers |
|---|---|---|
| Asset register | An equipment list in a spreadsheet | What do we own, where is it, what state is it in? |
| Work orders | Verbal instructions and paper job sheets | What is open, who has it, is it done? |
| Preventive maintenance | A wall calendar or a memory | Which services are due, and which are overdue? |
| Faults and inspections | Phone calls and checklists in a drawer | What broke, how long was it down, what did we find? |
| Spare parts | A storeman's notebook | What is in stock, and what was used on which machine? |
Everything else a CMMS offers, such as dashboards, reports, cost tracking or mobile apps, is built on top of those five. If a product is weak on the register or on work orders, no amount of reporting will fix it, because the reports will be summarising incomplete records.
CMMS, EAM and ERP: what is the difference?
The three terms overlap, and vendors use them loosely. A useful way to separate them is by the question each one is built to answer.
- CMMS answers: is the maintenance getting done? It focuses on work orders, schedules and the technicians doing the work.
- EAM (enterprise asset management) answers: what is each asset worth to us over its whole life? It adds procurement, costs, lifecycle decisions and often several sites.
- ERP (enterprise resource planning) answers: how is the business running? It covers finance, payroll and sales, and usually treats maintenance as a small module.
In practice most modern products sit between CMMS and EAM. The label matters less than whether the product keeps the asset record at the centre and lets the people in the field add to it.
When a spreadsheet stops being enough
Many teams run maintenance in a spreadsheet for years, and for a handful of assets with one person in charge that can be fine. These are the signs that it has stopped working:
- More than one person needs to update it, and copies start to disagree.
- Services are due on run hours or kilometres, so the schedule changes every time someone reads a meter.
- Nobody can say how long a machine was down last month, or what it cost to keep it running.
- Faults are reported by phone and the only record is whoever took the call.
- An auditor, insurer or client asks for a service history and it takes a day to put together.
How to choose a CMMS
Feature lists all look alike. These questions separate products that will be used from products that will be abandoned after the trial:
- Can the people in the field use it? If a technician cannot close a job or report a fault in under a minute, the records will stay empty.
- Does it schedule the way your assets wear? Plant and vehicles wear on hours and kilometres, buildings on the calendar. The system should handle both on the same asset.
- Can people outside the team report problems? Operators, cleaners and site staff see faults first. Charging a licence for each of them means they never report.
- Can you get your data out? You should be able to export every record, at any time, without asking.
- Can you start small? A free tier or a trial with your own assets tells you more than any demo.
Getting started without a big project
The most common reason a CMMS rollout fails is trying to load everything before anyone uses it. A better order is: register the assets that cause the most trouble, put a QR code on each, let anyone report a fault against them, and add preventive schedules once work is flowing. The history you build in the first month is worth more than a perfect import.