There are two sighs of relief every night in the life of an opera manager. The first comes when the curtain goes up . . . The second sigh of relief comes when the final curtain goes down without any disaster . . .
Source: in New Yorker, 17 Sep 1966.
-- Rudolf Bing, (Jan 9 1902-1997), Austrian-British manager; He was general manager of the New York Met (Metropolitan), 1950-1972; noted for controversial dealings with prima donnas.