A phrase often uttered by amateur bartenders who don't know what the hell they're doing, in order to gain the trust of a customer who doesn't know what they really want.
Customer: How do you know this drink will be good?
A tattooed apron wearing douchebag adorned with a quasi trendy moustache, usually wearing a page boy cap who significantly overcharges you for a gin and tonic with a rose petal in it whilst boring the fuck out of you about how he made his own campari
Q: Should we get some negronis?
A: NO! That bar spoon spinning hipster douche mixologist behind the bar will find some way to fuck up a three ingredient drink, call it a craft cocktail and charge us through the asshole for them. I will get a bottle of beer with the cap still on it if they can't fuck that up...