There’s not a living human being who doesn’t need luck. You need luck every time you give a concert. You worry about weather and transportation. Trains and planes are sometimes late; taxis have been known to break down. Then, at the hall, you worry that a string might snap or the lights fail, or that a page-turner might flip over two pages at once.

Jascha Heifetz (1901-1987) Lithuanian-American violinist

(Unsourced)

Quoted on his official web page.