Stainless steel knives can be soaked in use, cut acidic foods, dropped in the dishwasher and when they come out have not a stain or sign of rust on them, which is why the general public is endeared to them. Carbon steel is in fact superior in almost all ways save rust and patina. To know why, we need to look at the steel scientifically.
The rust resistance of stainless steel is due to Chromium. When Chromium is exposed to air, it bonds with the oxygen and creates an oxide, just like iron does (when iron bonds with oxygen, it becomes iron oxide, which we know as rust). Unlike iron however, chromium oxide is extremely hard and tough, so when chromium is exposed to air it gets a layer of super hard, microscopically thin chromium oxide (in fact, rubies and sapphires are made of chromium oxide). Because there is a layer of chromium oxide already there, more oxygen cannot come in to bond with the chromium beneath. With iron though, the iron oxide (rust) is very soft and flakes or falls off easily, exposing more iron to be oxidized, and so it gradually falls apart. Chemists in the late 1800’s figured this out, and started to add a small bit of chromium into the steel mix. This chromium created a layer on contact with air, which protected the steel from further oxidization.
The problem with chromium though, is it hinders the effect of Carbon, which hardens the steel, thus making it nigh impossible to get as hard as a pure carbon-iron steel mix. The harder a steel is, the harder it is to dull the blade. The pure carbon and iron mix can be manipulated quite easily, which also means the knife is going to be very tough. Carbon steels can also be gotten a lot sharper, as the steel doesn’t get ground away or domed on the edge when sharpening as easily as a stainless knife will, due to the softness.
So even though Carbon steel knives need to be oiled and well cared for in storage, in use, carbon steel outperforms stainless, in both how well they can get the job done and how fast they can get the job done.