Wiktionary
n. (context idiomatic English) An orderly and uneventful departure, timed so as not to detract or distract. vb. 1 To exit or disappear in a quiet, non-dramatic fashion, making way for more interesting events. 2 (context imperative English) leave the scene, and don't make a fuss.
Wikipedia
Exit Stage Left is a play conceived by Paul O'Farrell and Ben Smithard from Ecclesfield School, which played the Edinburgh Festival Fringe in summer 2012 chiefly using 2011 Ecclesfield School drama students.
Usage examples of "exit stage left".
When you exit stage left, you'll be given a tape machine which is about the size of a box of popcorn.
I'll appeal, and under the new guidelines, my appeal has to be in the hands of the Capital Crimes Circuit Court within seven days or you exit stage left immediately.
Voltaire asked, Why do you wish to exit stage left with such unseemly haste?