It looks like some kind of mechanical damage or chewing by insects. The damaged area then gets colonized probably by bacteri or fungi. It is a common problem. Usually you can take off the damaged leaves and seal the cut ends with a fungicide. Check around for slugs and snails, they love succulents. Make sure the tools you use are sharp and clean. You can either flame the tool, use a new razor blade or spray with alcohol first. Resterilize between cuts so you don't move any contaminated material to a new location. Wash your hands or wear gloves and change them frequently to prevent transferring any contaminated sap.
Happy gardening in Hawaii. Gardens are where people grow.