Key points in this article
The light speaks
Status lights encode warnings most users never learn. The mistake is modifying behavior before understanding what the site conditions actually signal through that small colored panel, because a blink ignored today is a breakdown scheduled for tomorrow.
The sound view
Know the site conditions first. Learn the light language so a blink is read as guidance, not ignored as decoration that nobody on the team has bothered to explain, and a legend posted once prevents a hundred anxious phone calls.
Checks before change
Confirm what each state means, who responds, and the documented baseline. On an abnormal signal, stop and report rather than guess the meaning and risk a fault that was avoidable, because guessing at a warning is the most expensive way to be wrong. Guessing at a warning is the most expensive way to be wrong, and the light that someone finally explained is the one that prevents the breakdown the next person would have driven straight into.