That live boiling that some people call inhumane? That's it.

Lobster notoriously goes bad very quickly after dying, becoming mushy and gross. It takes mere hours after death for the body to decay with a distinct smell and taste of ammonia, with the Vibrio bacteria causing food poisoning as well. Cooking lobsters alive has been done since Roman times, but not consistently.

Because lobsters need to be boiled alive (or frozen immediately upon death to stay fresh), lobster became known as a horrid trash crustacean only suitable for the poor. They were incredibly common, but disgusting. The only people who would eat them had nothing else to eat.

This began to turn around in the late 19th century thanks to the advent of modern food preservation. Frozen and canned lobster could be transported great distances inland, even all the way to the other coast, and its novelty in these normally lobster-free areas helped it become a delicacy. The same thing happened with oysters, which were also regarded as a semi-gross food for commoners before they could be shipped on ice even to desert saloons. Turning lobster into a delicacy also meant popularizing the proper way to cook it, which completely turned around its reputation.