I was digging through my drawer of electrical plugs to repair and old appliance when it struck me how decorative many of the old bakelite and rubber plugs were. Aside from the functionality of having grooves on them to help with pulling them out of outlets, there are some clear art deco influences happening in many of the examples above and below.
Apparently, this level of detail disappeared when industrial designers embraced something called "the concept of functional beauty" or "modernism" which came into place after World War II. That was a design philosophy that held that if something is made just to serve a purpose, then it can be beautiful without any decoration. But look at the octopus plugs below. I'll tell you which ones I think are more attractive.