not know what you're missing

not know what (one is) missing

To fail to realize how great something is because one refuses to try or participate in it. This movie is really interesting—you kids don't know what you're missing! A: "I've always been too nervous to try skydiving." B: "You don't know what you're missing. It's the thrill of a lifetime!"
See also: know, missing, not, what
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

not know what you’re ˈmissing

not realize how good, amusing, interesting, etc. something is because you have never tried it: ‘I’m not really interested in snowboarding.’ ‘Oh, you should give it a try. You don’t know what you’re missing.’
See also: know, missing, not, what
Farlex Partner Idioms Dictionary © Farlex 2017
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