It's not a pretty sight...
This is from wikipedia
Cauliflower ear (also hematoma auris or perichondrial hematoma) is a condition most common among wrestlers, rugby players, mixed martial artists, and boxers. If the external portion of the ear suffers a blow, a blood clot or other fluid may collect under the perichondrium. This separates the cartilage from the overlying perichondrium that is its source of nutrients, causing the cartilage to die. This leads to a formation of fibrous tissue in the overlying skin. When this happens, the outer ear becomes permanently swollen and deformed, thus resembling a cauliflower.
Headgear that protects the ears is worn in wrestling and rugby (where it is called a "scrum cap"), many martial arts, and other contact sports to help prevent this condition.
Cauliflower ear is often the source of pride for wrestlers and fighters. Thus, they disdain the protective gear[1].