the bottom falls out of something

the bottom falls out of something

If the bottom falls out of a market or industry, people stop buying its products in as large quantities as they did before. But just as quickly, the bottom fell out of the American home video game market. Note: You can also say that the bottom drops out of a market or industry. By the late seventies the bottom dropped out of the steel industry and heavy industry in general.
See also: bottom, fall, of, out, something

the bottom falls (or drops) out of something

something fails or collapses totally.
See also: bottom, fall, of, out, something