EXPLANATION Most adjectives have three degrees of comparison. For example, we can say that conditions were wet, at another time they were wetter and at another time they were wettest. The three degrees are wet, wetter, wettest. However, some adjectives cannot be compared. If something is unique, for example, it is the only one. It does not make sense to say that something is more unique than something else, because unique (which comes from the Latin word uni, meaning one) means that there is only one. Similarly, one cannot compare words such as perfect. A thing is either perfect or it is flawed. It cannot be more perfect because perfect means that something cannot be made better.
In other words, for absolute adjectives, there are no second or third degrees of comparison. We cannot say more unique, most unique or more perfect, most perfect.