It refers to the situation where the eyeball is positioned higher, and the left, right, and under parts of the eye are all white, hence called a three-white eye. You can try by yourself to look up, when the eyeball moves to the top, the lower part will naturally show the white.

Women with a lower three-white eye have a strong personality, a very strong sense of self, and when problems arise, they always blame others. Focused on material life, they are typical hedonists. They look down on others from the bottom of their hearts and often think only of themselves, thus easily becoming isolated. Women with this face reading like to control others but are also loyal and value principles. In work, they are especially hardworking and may not hesitate to use any means to achieve success. In middle age, they are prone to marital changes, and if they cannot adjust their emotions, they will inevitably fall deeper into the quagmire.
Women with a lower three-white eye have strong confidence, are bold and careful, yet cold-hearted, capricious, and often inconsistent in their behavior. They have a strong suspicion, are jealous, slightly neurotic, and do not understand or empathize with others, often betraying others. These people often encounter unexpected disasters.
In summary, from today's perspective, women with a lower three-white eye just have a rather strong personality, lack understanding of others, and lack the characteristics of caring for others. If these bad personalities can be slightly improved, everything will be fine. Therefore, the saying that lower three-white eyes are bad for husbands is incorrect. It is true, however, that they are not easy to get along with their husbands.