The shave brush lifts the whiskers an massages the skin. it also helps to clean away dead skin cells so they do not get in the way. As to soap in a can, I have not used it since I got my brush, but I personally do not think it is that bad (others on the site will probably throw things at me now). The brush will work even with the prefoamed stuff in a can, or you can use your fingers to work the lather into your whiskers, what is really not good is just slapping it on your face then shaving.