Why do you get the blues, are green with envy or red with rage.
Colour is a truly human experience and the development of pigments and dyes goes back to the origins of man and the trade in the rarest ingredients made kingdoms rise and fall.
While the perception of a colour is subjective, some colour effects have a more universal meaning like blue is a cool colour based on the physical relationship with water and the sky or red is a warm colour with its connection to fire. A second area to consider is that the perception of colour is culturally based. These emotional associations I will speak of come from a western aspect (for more in-depth on the cultural significant of colour there are great articles like this one).
As designers we can use these tools and pre-existing preferences to colour to our advantage. You want an exciting experience use lots of warm colours like red or to demonstrate credibility and professionalism lots of blue.
One of the easiest ways to do AB testing is simply swapping out colours and getting users to react based on as simple a change as that.
Mere colour, unspoiled by meaning, and unallied with definite form, can speak to the soul in a thousand different ways. ― Oscar Wilde
There has been a proven scientific connection between the colour of products and the urge to purchase. Every time you see a colour, there’s a chain of reactions taking place within the hypothalamus in your brain. Hormones are released to your thyroid, thus triggering emotions that affect your behaviour. In fact, 62% to 90% of purchasing decisions is based on colours! So, digging deeper into the psychology of colour can significantly improve elusive conversions for your website.
The right colour palette can give your product or service a greater chance of recognition and respect from you chosen audience .
Its these colour perceptions that brands use all the time to align themselves with and use emotions to connect with their customers.