The factory was incredibly clean. This maquiladora in northern Mexico was machining and assembling oil pumps, normally a very dirty process. Powered conveyor lines moved products from station to station as tools cut metal with coolant and hydraulics press-fit components together. There was not any oil on the floor, nor were there puddles of coolant or half-filled containment moats around machines. No metal shavings, parts, or components were on the floor.

I stood in the heart of the operation and looked around in amazement. My five years in high-volume machining conditioned me to expect coolant-soaked floors covered in metal shavings and puddles of oil. I congratulated the management team on having an outstanding facility and employees. I thought I was looking at the best 5S program that I had ever seen.

The five S’s are Sort, Set In order, Shine, Standardize and Sustain. The 5S’ are used to make abnormalities apparent. The standards are so clear, that when something is off-standard, it jumps out and starts investigation and problem solving.

A slogan for 5S might be “fix the small things and the big things fix themselves.” Five S is a foundation for other improvements because it demonstrates the employee and organizational self-discipline that is required for other continuous improvement tools to be effective. The 5S program establishes the standards for what belongs, where it belongs, ensures equipment and tools are inspected and ready for use, and constantly root causing and fixing the sources of contamination; it therefore creates a very neat and clean environment. Neat and clean is not the goal of 5S, but it is an outcome and allows us to easily see if things are to standard and quickly address failures.

As I stood in the hum of machines and conveyors machining and assembling products, I suddenly saw a finished oil pump assembly snag and get thrown from the conveyor. The part crashed to the floor and almost immediately two employees sprang from the back of plant to where the part lay. These were not production workers, or management, or material handlers. They were cleaners. They quickly scooped up the part, swept the floor, and ensured that there was no oil or grease remaining.

In minutes the scene was spotless. The perfect crime had been committed; no evidence remained, no report was completed, and no authorities notified.

Now my eyes were open. If a drop of oil leaked from a machine, a cleaner wiped it away within minutes. A part on the floor was immediately thrown into the trash. Coolant spray across the aisle had mops swinging. Nothing was investigated. Nothing was root caused. Nothing was fixed. They had a fantastic housekeeping program, but no 5S.

In a great 5S program, small amounts of oil would have been discovered on the connector or gasket (a Class I leak) during their inspection, or “Shine” step. A good 5S program would have started the maintenance request when there was a drop of oil forming, before it dripped to the floor (a Class II leak). An average 5S program would start an investigation when there is a drop of oil on the floor (a Class III leak) to find the source and begin the corrective actions. A housekeeping program will clean up the oil and make the problem invisible until when the machine seizes after running out of oil.

Without being able to see and fix small problems, the factory would have many big problems. Without any reports, there was not any way to determine how much scrap was produced, where scrap was produced, what machines leaked, where machines leaked, which coolant lines needed to be replaced, or which conveyor lines were dropping parts. The housekeeping program was so good that it actually prevented 5S problem solving and problem prevention.

Robert H. Simonis is the senior manufacturing and operations consultant at KCE Consulting LLC. Robert has over 20 years of leadership experience including 10 years in manufacturing management and 10 years of global responsibilities in automotive, electronics, machining, and complex assembly operations, and is recognized as a lean enterprise expert. Email or