Because the socket is powered on, there are two on and off above. If you want to use the socket, you must open the switch above, and the phenomenon of lights in the middle indicates that it has been powered on. If it is not bright, it means that there is no electricity and it will not charge the phone normally. It's the message that comes with each outlet. No one would know if it was on or off without those cues and it wouldn't say red light, no red light. It's impossible to tell.