It's really not bad. It's also, true, good for you. Mama was right. Liver is the Rodney Dangerfield of food, the spinach of meats. Those who like it are a lonely lot.
Few restaurants offer it.
Some grocery chains no longer even sell it. A cookbook is all-inclusive if it offers even one liver recipe. Many people are turned off by the very thought of eating innards like a heart or intestine or gland. Second, it's ugly. No matter how liver is cooked, it just doesn't appear as appetizing as a piece of roast chicken or a steak.