Physiologically, this is caused as the photopupillary reflex struggles to adapt the pupil to contradicting signals. Initially, this will result in an uncomfortable sensory overload and typically the pupil will take around 5 minutes to constrict. However, as the human eye only has a limited contrast ratio, this will leave the entire scene darker.
Continued exposure to glare results in fatigue, headaches and decreased workplace productivity. It doesn’t take much imagination to establish a direct link to profitability.