Around the country, they're denoted with stars or forks or spoons.
In Philadelphia, they're indicated with bells.
When Inquirer restaurant critic Craig LaBan sums up sentiment about a restaurant he is reviewing, he uses that cracked but uniquely Philadelphia icon. His scale is zero to four bells.
If you're a restaurateur knowing that your review is coming up, it's all you think about. Even if you have four. Ask Georges Perrier, whose demotion of Le Bec-Fin from four bells to two in 2012 helped set the stage for the landmark's closing.
This weekend, the steak/seafood house Ocean Prime - which opened in September at 15th and Sansom Streets - became the 16th restaurant in 15 years to receive no bells from LaBan, the region's most widely read and quoted critic.
So just how does a restaurant achieve no bells?
"It's a restaurant that has, on the course of multiple visits, been deficient in numerous aspects," LaBan told me Friday. "There's an epic badness to it."
"Usually it's a matter of dashed expectations from a talented name, or high menu prices that can't be justified, or the service ends up being offensive or a combination of all three. It's a restaurant with almost nothing I liked about it - bad with a side of offensiveness. It's never one dish, never one person, never one thing."
LaBan called his job public service, regardless of the review. He spends company money on his meals, but "I manage a budget for my job like people manage their own household budget. ... I do spend my own money on many meals that aren't necessarily included in Sunday reviews, and I remain very sensitive to the value of what quality costs at all its levels of ambition."
In the case of a no-bell experience, "I imagine a reader [going there] and saying to themselves, 'I wish someone had told me not to go there.' That's my rule."
He said he spent more cash at his multiple visits to Ocean Prime than he had spent on any other review in 2013. He declined to say how many visits he made, but said he sampled most of the menu.
LaBan said he would discuss the review at his online chat at 2 p.m. Tuesday.
Is a no-bell the kiss of death? Not necessarily, given the usual churn of the restaurant business. And, you could also argue, the graveyard of failed restaurants is filled with those he awarded two and three bells.
Many underperforming restaurants get their second chances relatively soon during his annual Year in Bells column, for which he goes back and eats again. This year's roundup runs on Dec. 29. Because Ocean Prime's review ran so close to the end of the year, though, it will have to wait for a future opportunity, he said.
Besides Ocean Prime, four other no-bell recipients - Serafina (2011), Liberte (2011), Del Frisco's (2009) and The Saint James (2013) - are still open. Liberte, inside the Sofitel, is now a lounge, not a full service restaurant.
Thai Kuu in Chestnut Hill initially received no bells in 2011 but was upgraded after a subsequent visit.
Chew Man Chu in Center City folded quickly after its no-bell in 2010.
In 2009, Del Frisco's in Center City - across the street from Ocean Prime - got one bell. LaBan demoted it to no bells after his year-end revisit.
Chima in Center City initially received no bells in 2008 but saw an upgrade to one bell after a revisit.
Javier in Haddonfield lasted a year after its no-bell in 2008.
Haru in Old City stuck around for six years after its 2005 no-bell.
Carmella's in Manayunk gave it up quickly after its 2003 no-bell.
Trust in Center City initially got no bells in 2002 but was upgraded to one bell; it lasted a year after the no-bell.
Shula's lasted six more years at the former Wyndham Franklin Plaza Hotel after its 2001 no-bell.
The Ivy Grille at the Inn at Penn lasted for two years after its 2000 no-bell.
LaBan awarded no bells to Old Original Bookbinder's in Old City in 1999; he eventually gave it one bell and then a second bell at its revival in 2005.
His first no bell was 1998 with Solaris Grille in Chestnut Hill; the restaurant remained open for nearly 13 years after that.
There are five current four-bell restaurants: Bibou, Fountain, Talula's Table, Vetri and Zahav.
Ocean Prime management declined to speak with me about the review.
But some restaurants laugh it off. In March 2009, in his one-bell review of Del Frisco's, LaBan snarked that it was the "female guests who were really turning heads, with so many surgically enhanced, body-glittered bosoms on display, the only thing missing was a brass pole."
So the steak house installed one and dedicated it to him. For his Year in Bells round-up in December, he demoted Del Frisco's to zero bells, saying that his "year-end revisit was even worse, with several dishes bordering on inedible, from a wickedly oversalted asparagus bisque to rubbery shrimp cocktail (drenched in gooey sauces), grease-soaked giant onion rings, and a $39.95 strip steak dredged in so much black pepper that it had to be recooked."
It's still open, four years later.