Actors and musicians have a saying about the difference between New York City (Broadway) and Los Angeles (Hollywood):
 
“In New York, they tell you that you suck and they stab you in the heart. In Los Angeles, they tell you that you’re great and they stab you in the back.”
 
The saying has been cited in print since at least 2012 and is of unknown origin.
 
   
MFA to LA
Are You Being Served
POSTED ON NOVEMBER 10, 2012 BY TIMOTHYTAMISIEA
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In other words, Phylis Ravel always had this stubborn jackass’s back.  Always.  In many ways, she knew me better than I did.  She understood my talent (“Timmy, I’m casting you in Hedda Gabler – it’s a dramatic role.  Deal with it.), my desires, (Timmy this is the difference between New York and LA.  In LA, they tell you how great you are and as soon as you turn around they stab you in the back.  In New York, they look you in the eye and say you suck and stab you in the heart.  Where do you want to go?”) and my wanderlust (Mr. Tamisiea!  Why are you’re studying abroad?”  “Cause I want to.”  “Oh.  Okay.”).
   
news.com.au
J.K. Simmons says Fletcher in Whiplash right about language’s worst two words
By VICKY ROACH National film writer
OCTOBER 23, 2014 12:00AM
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The brutal honesty of the cut-throat New York jazz scene is legendary.
 
“That’s kind of an east coast/west coast thing,’ says Simmons. “There’s an old saying that goes: In New York you might get stabbed in the heart, in LA you might get stabbed in the back.”