When lean manufacturing machine downtime becomes a problem a different approach to maintenance is required.
The common focus is changed from fixing breakdowns to preventing them. To do this a process needs to be developed to transfer the skills between machine operators and maintenance people.
Since operators are closest to the machines, they must be included in maintenance and monitoring activities in order to prevent and provide warning of malfunctions. The machine operator stays and helps when the machine breaks down, learns how to do some of the routine maintenance tasks like cleaning, and detecting abnormal conditions early.