Telltale signs that you’re in a bad restaurant

Three signs you need to leave a restaurant now!
Three signs you need to leave a restaurant now!

If you've ever dined out, you've probably walked into a restaurant, turned around and walked right out. Maybe it's something subtle, such as the lighting, or maybe it's something more obvious, such as a large rat. But whatever it is, you flee with the determination of a rush-hour commuter chasing a departing bus.

People in the restaurant business have been known to scurry for the exits, too. Restaurateur Joe Bastianich, chef Tim Love and pastry chef Waylynn Lucas of CNBC's "Restaurant Startup" unanimously cited their three warning signs of a category five culinary nightmare: the smell, the filth and the greeter, or lack thereof.

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"Bad smell," Love said. "Two, dirty kitchen or dirty floor. … And the third one is if somebody doesn't greet you, that just wears me out."

"If someone greets me at the door with a bad attitude, I don't care how good the food is, I don't care who the chef is, I am turning around and walking out the door," Lucas said.

While Bastianich was on board with all three grievances, he had his own list of things that he found objectionable enough to leave a restaurant over.

"The first thing, if there's an aquarium in the dining room, run like hell," he said. "Second rule of the restaurant, if the maitre d' is wearing a lapel pin, run like hell. ... The third and most vital sign is when they hand you the menu, if there's any food stains on the menu, put the menu down and leave."

"Restaurant Startup" is on a quest to discover, invest in and launch America's next generation of epicurean superstars. Tuesdays at 10 pm ET/PT.