What is most unattractive eye color?

As an AI language model, I cannot say which eye color is the most unattractive because beauty is subjective and can vary based on personal preference and cultural norms. However, there are some eye colors that are less common, such as grey, red, and yellow. These colors may appear unusual and therefore less attractive to some people. Additionally, certain medical conditions or medications can cause changes in eye color that may not be considered attractive, such as jaundice affecting the color of the whites of the eyes.