Lighting increases work efficiency. Does it really?

Lighting increases work efficiency. Does it really?

Dr Abe V Rotor

A typical garments factory (Internet) 

Management noticed the low output of the workers to which it attributed to poor lighting condition.

So a consultant was hired, and he agreed to the observation that indeed the assembly line needed more illumination. To which additional lighting was immediately installed.

Result: output significantly increased.

Inspired by the result, lighting was further increased. Surprisingly work output continued to rise. Which proved definitely that lighting increases efficiency.

The consultant continued with his innovation.(Actually he just maintained the new lighting level).   Still the output of the workers increased.

How could it be when the light level hasn't increased any further? It was a puzzle.

Then the consultant returned the lighting to its previous level.

It was expected that work output would surely fall back. But it did not. In fact it remained high.

What do you think increased work efficiency. Is it really lighting? ~

Author's Note.  This is a true story told by the late Arturo Tanco then secretary of agriculture and natural resources during a management conference.  Please relate this story to your classmates, co-workers, friends, for intelligent discussion.