With today's machine-produced wine bottles, concave bottoms no longer seem to serve much of a purpose, particularly when it comes to still wine. Is it merely tradition, or something else entirely? For instance, some people mistakenly assume that a concave bottom is an indicator of quality. Wines with concave bottoms are not necessarily better than their flat-bottomed counterparts. Rather, they can be part of a sneaky marketing scheme: a big punt means a larger bottle (and larger price tag) for the same amount of wine!