Before a Kohen declares that a garment has Tzaraat, he has to check it one final time to make sure that the appearance has not changed. When the Torah relates this information, it uses an interesting choice of words. It states (VaYikra 13:55), “Lo Hafach HaNega Et Eino”, which literally translates as, “the affliction has not changed its eye.” Why would the Torah use the word “eye” to mean “appearance”?
On this topic, the Chiddushei HaRim notes that Lashon HaRa was not the only Aveirah for which a person could receive Tzaraat. The Gemara (Eirchin 16a) states that there were actually seven Aveirot that could cause a person to receive Tzaraat. One of them was Tzarut HaAyin, which means one who is mean, stingy, and looks on the world with a negative perspective.
A Tzar Ayin can do Teshuvah, however, and become a Tov Ayin—one who is positive about life, generous, and happy. A Tov Ayin is just the opposite of a Tzar Ayin. He, unlike the Tzar Ayin, would see the glass as half full and not half empty.
This explains why the Torah uses the word “Eino.” If the mean person does not change his ways to become a nice, cheerful Tov Ayin, his garments will be infected by Tzaraat and burned. However, the reason the Kohein checks one last time is to see if the person changed his personality for the better. If he did, then the affliction will leave the garment and it will be Tahor.