This may not be what you expected, but sweat is not the cause of body odor. It is the bacteria that gets trapped within the moisture that creates the unpleasant smell. A 2016 medical study reported Corynebacterium is the bacteria found in the moisture of your armpit, along with Staphylococcus, Propionibacterium, and Micrococcus.
These bacteria become trapped within the moist dark crevice of your armpit creating the perfect environment for more bacteria to breed. If the bacteria is not properly cleansed from your armpits each time you shower, you are not applying your deodorant to a clean environment! Therefore, I found the key to controlling underarm odor is proper cleansing.