Poor lighting not only makes it hard to see and concentrate properly but the poor lightning can also cause other health issues.
If you work in an office with poor lightning and are staring at a computer screen the poor lightning can give you headaches and make it hard to concentrate on what you're doing on the computer screen.
I used to work in an office with poor lightning and had to be at a computer all day and the poor lightning while looking at the bright computer screen gave me headaches and I had to look away from the computer as often as I could.
Finally we got some better lightning in the office and my headaches went away and my productivity went up.
Poor lightning can also cause things such as depression, eyestrain etc.
It can also cause neck pain, back pain and even should pain and shoulder strain because you need to sometimes stretch to see things.
If you work in another workplace and have poor lighting it could cause you to drop things, get hurt by tools, cause you to fall, trip or even slip.
Good lighting is essential to our health and well being especially if you work in an office on a computer because you'll suffer from eye strain if you don't have good lightning.