Many people believe that the size of a wine bottle's punt relates to the plonk's quality, with better wines supposedly having deeper indentations on the bottle.
But expert Dr Vinifera, aka Dr Vinny of Wine Spectator, says that this hole at the bottom of the bottle has nothing to do with how good the wine tastes.
The anonymous wine expert says: "The size of the punt doesn't mean anything about the quality of the wine inside, but it can be a bit gimmicky, because some bottles just look like they're on steroids, with deep punts and extra-heavy glass."
The critic makes the point that some of the best Champagnes in the world don't have indentations on the bottom of the bottles.
The real reason why bottles have a punt is historical, Dr Vinny says.
Punts were put in place by glassblowers to make sure the bottles could stand upright.
Now most bottles are of course machine-made - but winemakers still add them to continue the tradition.
Dr Vinny says: "Historically, punts were a function of wine bottles being made by glassblowers. The seam was pushed up to make sure the bottle could stand upright and there wasn't a sharp point of glass on the bottom.
They added: "Punts no longer serve a structural function except in bottles of sparkling wine, which have constant pressure inside. In these cases, the punt allows for more even distribution of pressure."