There are only a few real reasons to send a wine back: if it’s not the wine you ordered, if it’s not the year you ordered (vintages vary wildly, so getting the advertised year is important) or if there is something technically wrong with the wine.

Says Pelagia Chef Fabrizio Schenardi, “The wine can be tricky sometimes, because there are a lot of things that can be wrong. The worst thing for a wine is for it to be corked. Then it is perfectly fine to send it back.”

A corked wine is simply a wine that has a defective cork. You’ll know this because when you are presented with the cork it may be mildewy smelling and excessively wet or bloated on one end. The wine itself will have a wet cardboard smell. Once you suspect this is the problem, call it to your waiter or sommelier’s attention, asking them to smell or taste the wine, too. Almost every restaurant will take back a corked wine.

Black Pearl’s Kathleen LaRoche assures, “When someone sends a wine back, we get credit for those bottles. Whether it was corked or the customer did not like it, we get credit from our distributor.”

A wine may also be oxidized, which means oxygen in the bottle is slowly ruining the wine, changing its color and lending it a weak vinegar smell. This is often the case with wines by the glass, where a half-empty bottle has been kept out on the bar for a couple days, “breathing” the air in the bottle.

Ellen Zusman, owner of ImaginEats, says, “Wines by the glass are often bad, but I’ve sent my fair share of bottles back too, mostly because restaurants don’t store their wine properly.”

Zusman is referring to eateries that may not keep their wine inventory in temperature- and humidity-controlled environments. Wines suffer when put through repeated temperature fluctuations, or when stored at high temperatures. Wines like this are sometimes referred to as “cooked.” Imagine a Florida summer weekend with the air-conditioning off, bottles left to swelter in a hot restaurant storage room.

A cooked wine will look brownish around the edges of the glass, red or white, and it may smell caramelized, like a cheap sherry. A red may take on a rusty color, while a white deepens to a dark yellow.

Winemakers can make mistakes, too: If a bottle is fizzy and it’s not a sparkling wine, it has gone through an unexpected second fermentation in the bottle. And if a wine smells rotten eggy, this means the winemaker had an overly heavy hand with the sulfur dioxide. A mistake.

Sniff, sip and send it back if you detect any of these problems, and stand firm if your waiter is skeptical.

Still, Marlin Darlin’s Tom Pritchard notes, “Bern Laxer [of Bern’s Steak House] was a friend of mine. Bern felt that if you buy a $1,000 bottle of wine and you say you don’t like it, but the sommeliers says it’s OK, you’re paying for it. In our restaurants, the average bottle of wine is about $40, so we’ll usually replace it.”