Idk how to explain this but it is about how intense the color is and how our brains receive it? red is blood red is anger red is love..ect it represent deep emotions and each color has its effect of us (scientifically on the brain) that's why u may trust a person wearing green more or why we see black as mysterious and alluring or blue seem so calm
Things can varie from person to another tho

I cant for the life of me understand the way people talk about art. Like how tf does a red painting have emotions???????