Stainless steel access doors and cabinetry seem to be the most well known types of doors and cabinetry used in outdoor kitchens, however, stainless steel comes in a wide variety of types and costs. The best type of stainless steel for outdoor use is 304 series, because it is more corrosion resistant than other types. It’s also expensive.
Stainless steel, even 304 series, will stain, pit and corrode, and if it’s exposed to harsh elements like salt water, salt air, or chlorine, it will happen much faster. If you want to prolong the life of your stainless steel it will require regular maintenance. It is also difficult to keep clean, which is why there is an entire industry related to stainless steel cleaning products.