leave to chance

leave (something) to chance

To resign oneself to something's outcome being determined forces outside of one's control. My boss always scrutinizes the smallest details of any deal she makes—she says there's nothing more foolish than leaving things to chance in business. You could just pick a few different investments and leave the whole process to chance, or you could let our firm plan your investments meticulously in order to maximize your return.
See also: chance, leave, to
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

leave something to chance

to allow something to be settled by chance. Plan your day. Don't leave anything to chance. It is not a good idea to leave any of this to chance.
See also: chance, leave, to
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
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References in periodicals archive ?
But who runs the Lottery is too important to leave to chance and too important to leave to people few have confidence in.
"It seems it's far too important to leave to chance or indeed to men.